Bump actions/stale from 6 to 9 (#1405)

Author: dependabot[bot]

.github/workflows/stale.yml

@@ -13,7 +13,7 @@ jobs:
       pull-requests: write
 
     steps:
-    - uses: actions/stale@v6
+    - uses: actions/stale@v9
       with:
         repo-token: ${{ secrets.GITHUB_TOKEN }}
         days-before-stale: 10