docs: add G S keyboard shortcut for Security tab (#60098)

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content/get-started/accessibility/keyboard-shortcuts.md

@@ -51,6 +51,7 @@ The following sections list some of the available keyboard shortcuts, organized
 | {% endif %} |
 |<kbd>G</kbd> <kbd>W</kbd> | Go to the **Wiki** tab. For more information, see [AUTOTITLE](/communities/documenting-your-project-with-wikis/about-wikis). |
 |<kbd>G</kbd> <kbd>G</kbd> | Go to the **Discussions** tab. For more information, see [AUTOTITLE](/discussions/collaborating-with-your-community-using-discussions/about-discussions).
+|<kbd>G</kbd> <kbd>S</kbd> | Go to the repository's **Security** tab. For more information, see [AUTOTITLE](/code-security/getting-started/github-security-features).
 
 ## Source code editing