chore: bump actions/stale from 7 to 8 (#8)

Bumps [actions/stale](https://github.com/actions/stale) from 7 to 8.
- [Release notes](https://github.com/actions/stale/releases)
- [Changelog](https://github.com/actions/stale/blob/main/CHANGELOG.md)
- [Commits](actions/stale@v7...v8)

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

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

.github/workflows/maintenance.yml

@@ -8,7 +8,7 @@ jobs:
     name: "close stale issues and pull requests"
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/stale@v7
+      - uses: actions/stale@v8
         with:
           # On the 'debug' mode the action will not perform any operation.
           # Add the secret ACTIONS_STEP_DEBUG with a value of 'true' in the repository.