Add PR cleaner workflow

cleaner.yml

@@ -0,0 +1,19 @@
+name: 'Close stale PRs'
+on:
+  workflow_dispatch:
+  schedule:
+    - cron: '11 1 * * *'
+
+jobs:
+  stale:
+    runs-on: ubuntu-latest
+    permissions:
+      pull-requests: write
+    steps:
+      - uses: actions/stale@v7
+        with:
+          debug-only : false # Set to true to work in dry-run mode
+          stale-pr-message: 'This PR is stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 30 days.'
+          close-pr-message: 'This PR was closed because it has been stalled for 90 days with no activity.'
+          days-before-stale: 60
+          days-before-close: 30