Add a stale check to PRs and issues (as a dry run for now). (https://github.com/woocommerce/woocommerce-admin/pull/6082)

plugins/woocommerce-admin/.github/workflows/stale.yml

@@ -0,0 +1,24 @@
+name: 'Mark or close stale issues and PRs'
+
+on:
+    schedule:
+        - cron: '00 * * * *'
+
+jobs:
+    stale:
+        runs-on: ubuntu-latest
+        steps:
+            - uses: actions/stale@v3.0.14
+              with:
+                  repo-token: ${{ secrets.GITHUB_TOKEN }}
+                  days-before-issue-stale: 90
+                  days-before-pr-stale: 30
+                  days-before-close: 5
+                  stale-issue-message: 'This issue has been automatically marked as stale because it has not had any recent activity. It will be closed if no further activity occurs. Thank you for your contributions.'
+                  stale-pr-message: 'This PR has been automatically marked as stale because it has not had any recent activity. It will be closed if no further activity occurs. Thank you for your contributions.'
+                  close-issue-message: 'This issue was automatically closed due to being stale. Please feel free to re-open it if you still experience this problem.'
+                  close-pr-message: 'This PR was automatically closed due to being stale.'
+                  stale-pr-label: 'status: stale'
+                  stale-issue-label: 'status: stale'
+                  exempt-issue-labels: 'cooldown period,priority: high,priority: critical'
+                  debug-only: true