[ci] Adding autoclose stale PRs/Issues

Author: romainr

.github/workflows/autoclose-stale.yml

@@ -0,0 +1,17 @@
+name: 'Close stale issues and PRs'
+on:
+  schedule:
+    - cron: '30 1 * * *'
+
+jobs:
+  stale:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/stale@v3
+        with:
+          exempt-milestones:
+          exempt-issue-labels: 'roadmap'
+          exempt-pr-labels: 'roadmap'
+          stale-issue-message: 'This issue is stale because it has been open 30 days with no activity. Remove stale label or comment or this will be closed in 5 days.'
+          days-before-stale: 30
+          days-before-close: 5