[CodeQL] Added notification to slack on job failure (#210962)

## Summary

Added notification to slack on job failure.


__Closes: https://github.com/elastic/kibana/issues/210957__

---------

Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com>

.github/workflows/codeql.yml

@@ -31,7 +31,6 @@ jobs:
       with:
         languages: ${{ matrix.language }}
         config-file: ./.github/codeql/codeql-config.yml
-        debug: ${{ matrix.branch != '7.17' }}
 
     # TODO: Possibly required to follow all call paths, however, when enabled, the step below runs out of memory.
     # Possible workarounds: Apply for access to the GitHub beta where we can use beefier machines, or run it ourselves on Buildkite
@@ -65,11 +64,20 @@ jobs:
         category: "/language:${{matrix.language}}"
         ref: ${{ env.CHECKOUT_REF }}
         sha: ${{ env.CHECKOUT_SHA }}
+    - name: Notify to slack on failure
+      if: ${{ failure() }}
+      uses: slackapi/slack-github-action@v2.0.0
+      with:
+        method: chat.postMessage
+        token: ${{ secrets.CODE_SCANNING_SLACK_TOKEN }}
+        payload: |
+          channel: ${{ secrets.CODE_SCANNING_SLACK_CHANNEL_ID }}
+          text: ":broken_heart: CodeQL analysis failed for ${{ github.repository }} on ${{ env.CHECKOUT_SHA }}."
   alert:
     name: Alert
     runs-on: ubuntu-latest
     needs: analyze
-    if: github.repository == 'elastic/kibana' # Hack: Do not run on forks
+    if: ${{ github.repository == 'elastic/kibana' && success() }} # Hack: Do not run on forks
     steps:
     - name: Checkout kibana-operations
       uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2