Add step to verify release notes files are correctly formatted (#8323)

* Add step to verify release notes files are correctly formatted

* Fake release note

* Trigger file

* Fix step not running when it should

* Fix release notes error

* Remove trigger files

.github/workflows/release_notes.yml

@@ -41,3 +41,8 @@ jobs:
             echo "::error::The release notes file is missing, please add one or attach the label 'ignore-for-release-notes' to this PR."
             exit 1
           fi
+
+      - name: Verify release notes formatting
+        if: steps.changed-files.outputs.any_changed == 'true' && !contains( github.event.pull_request.labels.*.name, 'ignore-for-release-notes')
+        run: |
+          yamllint -d "{extends: default, rules: {line-length: {max: 1200}}}" ${{ steps.changed-files.outputs.all_changed_files }}