Add branch restrictions to workflow_run trigger in ci-doctor workflow (#69)

Author: github-actions[bot]

workflows/ci-doctor.md

@@ -4,6 +4,8 @@ on:
     workflows: ["Daily Perf Improver", "Daily Test Coverage Improver"]  # Monitor the CI workflow specifically
     types:
       - completed
+    branches:
+      - main
     # This will trigger only when the CI workflow completes with failure
     # The condition is handled in the workflow body
   stop-after: +48h