ci: bump actions/stale from 8 to 9 (#7815)

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](https://github.com/actions/stale/compare/v8...v9)

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

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/repo-stale.yml

@@ -18,7 +18,7 @@ jobs:
         with:
           app_id: ${{ secrets.GH_APP_ID }}
           private_key: ${{ secrets.GH_APP_PRIVATE_KEY }}
-      - uses: actions/stale@v8
+      - uses: actions/stale@v9
         with:
           repo-token: ${{ steps.generate_token.outputs.token }}
           days-before-stale: 60