Check that PR titles do not reference issue (#8118)

.github/workflows/pr-conventions.yml

@@ -0,0 +1,19 @@
+name: PR Conventions
+
+on:
+  pull_request:
+    types: [ opened, synchronize, reopened, edited, labeled, unlabeled ]
+
+jobs:
+  pr-title:
+    name: "Title"
+    runs-on: ubuntu-latest
+    steps:
+      - name: Prevent issue reference in title
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const issueRegex = /#\d+/i;
+            if (issueRegex.test(context.payload.pull_request.title)) {
+              core.setFailed("Please mention the issue number in the PR description, not in the title. Make sure to write 'closes: #<number>'.");
+            }