Fix fromJSON crash in search indexing workflow when no failures exist (#60118)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: heiskr

.github/workflows/index-general-search.yml

@@ -295,7 +295,7 @@ jobs:
           } >> "$GITHUB_OUTPUT"
 
       - name: Close previous scraping failure issues
-        if: ${{ steps.check-artifacts.outputs.has_artifacts == 'true' && fromJSON(steps.aggregate.outputs.result).hasFailures }}
+        if: ${{ steps.check-artifacts.outputs.has_artifacts == 'true' && fromJSON(steps.aggregate.outputs.result || '{"hasFailures":false}').hasFailures }}
         env:
           GH_TOKEN: ${{ secrets.DOCS_BOT_PAT_BASE }}
           RUN_URL: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}
@@ -313,10 +313,10 @@ jobs:
           done
 
       - name: Create scraping failure issue
-        if: ${{ steps.check-artifacts.outputs.has_artifacts == 'true' && fromJSON(steps.aggregate.outputs.result).hasFailures }}
+        if: ${{ steps.check-artifacts.outputs.has_artifacts == 'true' && fromJSON(steps.aggregate.outputs.result || '{"hasFailures":false}').hasFailures }}
         env:
           GH_TOKEN: ${{ secrets.DOCS_BOT_PAT_BASE }}
-          FAILURE_MESSAGE: ${{ fromJSON(steps.aggregate.outputs.result).message }}
+          FAILURE_MESSAGE: ${{ fromJSON(steps.aggregate.outputs.result || '{"message":""}').message }}
           RUN_URL: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}
           FILE_URL: ${{ github.server_url }}/${{ github.repository }}/blob/main/.github/workflows/index-general-search.yml
           WORKFLOW_NAME: ${{ github.workflow }}
@@ -340,13 +340,13 @@ jobs:
             --body "$body"
 
       - name: Send consolidated Slack notification
-        if: ${{ steps.check-artifacts.outputs.has_artifacts == 'true' && fromJSON(steps.aggregate.outputs.result).hasFailures }}
+        if: ${{ steps.check-artifacts.outputs.has_artifacts == 'true' && fromJSON(steps.aggregate.outputs.result || '{"hasFailures":false}').hasFailures }}
         uses: ./.github/actions/slack-alert
         with:
           slack_channel_id: ${{ secrets.DOCS_ALERTS_SLACK_CHANNEL_ID }}
           slack_token: ${{ secrets.SLACK_DOCS_BOT_TOKEN }}
           color: warning
-          message: ${{ fromJSON(steps.aggregate.outputs.result).message }}
+          message: ${{ fromJSON(steps.aggregate.outputs.result || '{"message":""}').message }}
 
       - uses: ./.github/actions/slack-alert
         if: ${{ failure() }}