Test concurrency to kill previous running actions on brnach

.github/workflows/ruff.yml

@@ -3,9 +3,9 @@ on: [pull_request]
 jobs:
   ruff:
     runs-on: ubuntu-latest
-    #concurrency:
-    #  group: ${{ github.ref }}
-    #  cancel-in-progress: true
+    concurrency:
+      group: ${{ github.ref }}
+      cancel-in-progress: true
     permissions:
       # Give the default GITHUB_TOKEN write permission to commit and push the changed files.
       contents: write