add stale.yml

Change the cron schedule for closing stale issues and PRs.

Author: danadajian

.github/workflows/stale.yml

@@ -0,0 +1,15 @@
+name: 'Close stale issues and PRs'
+on:
+  schedule:
+    - cron: '0 0 * * *'
+
+jobs:
+  stale:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/stale@v10
+        with:
+          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-pr-stale: 7
+          days-before-pr-close: 7
+          days-before-issue-stale: -1