Bump actions/stale from 3 to 8

Bumps [actions/stale](https://github.com/actions/stale) from 3 to 8.
- [Release notes](https://github.com/actions/stale/releases)
- [Changelog](https://github.com/actions/stale/blob/main/CHANGELOG.md)
- [Commits](actions/stale@v3...v8)

---
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/stale-issues.yml

@@ -8,7 +8,7 @@ jobs:
   stale_issues:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/stale@v3
+      - uses: actions/stale@v8
         with:
           days-before-stale: 60
           days-before-close: 7