Code scanning GHAE - mention self-hosted runners' prerequisites (#23119)

* fix links in reusable and add prerequisites to the article on setting up code scanning

* change paras

* Add prerequisites section for GHAE

Author: mchammer01

content/code-security/code-scanning/automatically-scanning-your-code-for-vulnerabilities-and-errors/setting-up-code-scanning-for-a-repository.md

@@ -23,7 +23,6 @@ topics:
   - Actions
   - Repositories
 ---
-<!--For this article in earlier GHES versions, see /content/github/finding-security-vulnerabilities-and-errors-in-your-code-->
 
 {% data reusables.code-scanning.beta %}
 {% data reusables.code-scanning.enterprise-enable-code-scanning-actions %}
@@ -34,13 +33,21 @@ You decide how to generate {% data variables.product.prodname_code_scanning %} a
 
 {% data reusables.code-scanning.enabling-options %}
 
+{% ifversion ghae %}
+## Prerequisites
+
+Before setting up {% data variables.product.prodname_code_scanning %} for a repository, you must ensure that there is at least one self-hosted {% data variables.product.prodname_actions %} runner available to the repository. 
+
+Enterprise owners, organization and repository administrators can add self-hosted runners. For more information, see "[About self-hosted runners](/actions/hosting-your-own-runners/about-self-hosted-runners)" and "[Adding self-hosted runners](/actions/hosting-your-own-runners/adding-self-hosted-runners)."
+{% endif %}
+
 ## Setting up {% data variables.product.prodname_code_scanning %} using actions
 
 {% ifversion fpt or ghec %}Using actions to run {% data variables.product.prodname_code_scanning %} will use minutes. For more information, see "[About billing for {% data variables.product.prodname_actions %}](/billing/managing-billing-for-github-actions/about-billing-for-github-actions)."{% endif %}
 
 {% data reusables.repositories.navigate-to-repo %}
 {% data reusables.repositories.sidebar-security %}
-3. To the right of "{% data variables.product.prodname_code_scanning_capc %} alerts", click **Set up {% data variables.product.prodname_code_scanning %}**. {% ifversion fpt or ghes > 3.0 or ghae-next or ghec %}If {% data variables.product.prodname_code_scanning %} is missing, you need to ask an organization owner or repository administrator to enable {% data variables.product.prodname_GH_advanced_security %}. For more information, see "[Managing security and analysis settings for your organization](/organizations/keeping-your-organization-secure/managing-security-and-analysis-settings-for-your-organization)" or "[Managing security and analysis settings for your repository](/github/administering-a-repository/managing-security-and-analysis-settings-for-your-repository)."{% endif %}
+1. To the right of "{% data variables.product.prodname_code_scanning_capc %} alerts", click **Set up {% data variables.product.prodname_code_scanning %}**. {% ifversion fpt or ghes > 3.0 or ghae-next or ghec %}If {% data variables.product.prodname_code_scanning %} is missing, you need to ask an organization owner or repository administrator to enable {% data variables.product.prodname_GH_advanced_security %}. For more information, see "[Managing security and analysis settings for your organization](/organizations/keeping-your-organization-secure/managing-security-and-analysis-settings-for-your-organization)" or "[Managing security and analysis settings for your repository](/github/administering-a-repository/managing-security-and-analysis-settings-for-your-repository)."{% endif %}
  !["Set up {% data variables.product.prodname_code_scanning %}" button to the right of "{% data variables.product.prodname_code_scanning_capc %}" in the Security Overview](/assets/images/help/security/overview-set-up-code-scanning.png)
 4. Under "Get started with {% data variables.product.prodname_code_scanning %}", click **Set up this workflow** on the {% data variables.product.prodname_codeql_workflow %} or on a third-party workflow. 
  !["Set up this workflow" button under "Get started with {% data variables.product.prodname_code_scanning %}" heading](/assets/images/help/repository/code-scanning-set-up-this-workflow.png)Workflows are only displayed if they are relevant for the programming languages detected in the repository. The {% data variables.product.prodname_codeql_workflow %} is always displayed, but the "Set up this workflow" button is only enabled if {% data variables.product.prodname_codeql %} analysis supports the languages present in the repository.

data/reusables/code-scanning/enabling-options.md

@@ -1,8 +1,8 @@
 | <nobr>Type of analysis</nobr> | Options for generating alerts |
 |------------------|-------------------------------|
 {%- ifversion fpt or ghes > 3.0 or ghae-next %}
-| {% data variables.product.prodname_codeql %} | Using {% data variables.product.prodname_actions %} (see "[Setting up {% data variables.product.prodname_code_scanning %} using actions](/github/finding-security-vulnerabilities-and-errors-in-your-code/setting-up-code-scanning-for-a-repository#setting-up-code-scanning-using-actions)") or running {% data variables.product.prodname_codeql %} analysis in a third-party continuous integration (CI) system (see "[About {% data variables.product.prodname_codeql %} {% data variables.product.prodname_code_scanning %} in your CI system](/code-security/secure-coding/about-codeql-code-scanning-in-your-ci-system)").
+| {% data variables.product.prodname_codeql %} | Using {% data variables.product.prodname_actions %} (see "[Setting up {% data variables.product.prodname_code_scanning %} using actions](/code-security/code-scanning/automatically-scanning-your-code-for-vulnerabilities-and-errors/setting-up-code-scanning-for-a-repository#setting-up-code-scanning-using-actions)") or running {% data variables.product.prodname_codeql %} analysis in a third-party continuous integration (CI) system (see "[About {% data variables.product.prodname_codeql %} {% data variables.product.prodname_code_scanning %} in your CI system](/code-security/code-scanning/using-codeql-code-scanning-with-your-existing-ci-system/about-codeql-code-scanning-in-your-ci-system)").
 {%- else %}
-| {% data variables.product.prodname_codeql %} | Using {% data variables.product.prodname_actions %} (see "[Setting up {% data variables.product.prodname_code_scanning %} using actions](/github/finding-security-vulnerabilities-and-errors-in-your-code/setting-up-code-scanning-for-a-repository#setting-up-code-scanning-using-actions)") or using the {% data variables.product.prodname_codeql_runner %} in a third-party continuous integration (CI) system (see "[Running {% data variables.product.prodname_codeql %} code scanning in your CI system](/github/finding-security-vulnerabilities-and-errors-in-your-code/running-codeql-code-scanning-in-your-ci-system)").
+| {% data variables.product.prodname_codeql %} | Using {% data variables.product.prodname_actions %} (see "[Setting up {% data variables.product.prodname_code_scanning %} using actions](/code-security/code-scanning/automatically-scanning-your-code-for-vulnerabilities-and-errors/setting-up-code-scanning-for-a-repository#setting-up-code-scanning-using-actions)") or using the {% data variables.product.prodname_codeql_runner %} in a third-party continuous integration (CI) system (see "[Running {% data variables.product.prodname_codeql_runner %} in your CI system](/code-security/code-scanning/using-codeql-code-scanning-with-your-existing-ci-system/running-codeql-runner-in-your-ci-system)").
 {%- endif %}
-| Third&#8209;party | Using {% data variables.product.prodname_actions %} (see "[Setting up {% data variables.product.prodname_code_scanning %} using actions](/github/finding-security-vulnerabilities-and-errors-in-your-code/setting-up-code-scanning-for-a-repository#setting-up-code-scanning-using-actions)") or generated externally and uploaded to {% data variables.product.product_name %} (see "[Uploading a SARIF file to {% data variables.product.prodname_dotcom %}](/github/finding-security-vulnerabilities-and-errors-in-your-code/uploading-a-sarif-file-to-github)").|
+| Third&#8209;party | Using {% data variables.product.prodname_actions %} (see "[Setting up {% data variables.product.prodname_code_scanning %} using actions](/code-security/code-scanning/automatically-scanning-your-code-for-vulnerabilities-and-errors/setting-up-code-scanning-for-a-repository#setting-up-code-scanning-using-actions)") or generated externally and uploaded to {% data variables.product.product_name %} (see "[Uploading a SARIF file to {% data variables.product.prodname_dotcom %}](/code-security/code-scanning/integrating-with-code-scanning/uploading-a-sarif-file-to-github)").|