ci: bump actions/stale from 6 to 7

Bumps [actions/stale](https://github.com/actions/stale) from 6 to 7.
- [Release notes](https://github.com/actions/stale/releases)
- [Changelog](https://github.com/actions/stale/blob/main/CHANGELOG.md)
- [Commits](actions/stale@v6...v7)

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

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/stale.yml

@@ -18,7 +18,7 @@ jobs:
       pull-requests: write
 
     steps:
-    - uses: actions/stale@v6
+    - uses: actions/stale@v7
       with:
         repo-token: ${{ secrets.GITHUB_TOKEN }}
         days-before-stale: 60