ci(stale): dry-run(!) enable github stale action to mark stale issues…

… & PRs after 60 days and then close them after another 7 days

See https://github.com/actions/stale

See #2747

.github/workflows/stale.yml

@@ -0,0 +1,16 @@
+name: 'Remove labels when the issue or PR becomes stale'
+on:
+  schedule:
+    - cron: '30 1 * * *'
+
+permissions:
+  issues: write
+  pull-requests: write
+
+jobs:
+  stale:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/stale@v8
+        with:
+          debug-only: true