Bump actions/stale from 8 to 9

Bumps [actions/stale](https://github.com/actions/stale) from 8 to 9.
- [Release notes](https://github.com/actions/stale/releases)
- [Changelog](https://github.com/actions/stale/blob/main/CHANGELOG.md)
- [Commits](actions/stale@v8...v9)

---
updated-dependencies:
- dependency-name: actions/stale
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/stalled.yml

@@ -17,7 +17,7 @@ jobs:
           private_key: ${{ secrets.APP_PRIVATE_KEY }}
           installation_id: 22958780
       - name: Stale PRs
-        uses: actions/stale@v8
+        uses: actions/stale@v9
         with:
           repo-token: ${{ steps.github_app_token.outputs.token }}
           stale-pr-label: 'stalled'