ci: added close stale issue workflow

.github/workflows/close-stale-issue.yaml

@@ -0,0 +1,20 @@
+name: 'github-close-stale'
+on:
+  schedule:
+    - cron: '30 1 * * *'
+
+jobs:
+  stale:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/stale@v3
+        with:
+          repo-token: ${{ secrets.GH_PAT }}
+          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 7 days.'
+          stale-pr-message: 'This pr is stale because it has been open 30 days with no activity. Remove stale label or comment or this will be closed in 7 days.'
+          close-issue-message: 'This issue was closed because it has been stalled for 7 days with no activity.'
+          close-pr-message: 'This pr was closed because it has been stalled for 7 days with no activity.'
+          days-before-stale: 30
+          days-before-close: 7
+          exempt-issue-milestones: 'future-release'
+          exempt-pr-milestones: 'future-release'