ci: setup stale issue workflow (#1795)

Author: kerwanp

.github/workflows/issue-stale.yml

@@ -0,0 +1,23 @@
+name: Close inactive issues
+on:
+  workflow_dispatch:
+  schedule:
+    - cron: "30 1 * * *"
+
+jobs:
+  close-issues:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/stale@v9
+        with:
+          stale-issue-message: "This issue is stale because it has been open for 90 days with no activity. If there is no activity in the next 7 days, the issue will be closed."
+          close-issue-message: "This issue was closed because it has been inactive for 7 days since being marked as stale. Please open a new issue if you believe you are encountering a related problem."
+          ascending: false
+          operations-per-run: 300
+          days-before-issue-stale: 90
+          days-before-issue-close: 5
+          days-before-pr-stale: -1
+          days-before-pr-close: -1
+          stale-issue-label: "stale"
+          exempt-issue-labels: "Issue accepted"
+          enable-statistics: true