Bump actions/stale from 4 to 9 (#36)

* Bump actions/stale from 4 to 9

Bumps [actions/stale](https://github.com/actions/stale) from 4 to 9.
- [Release notes](https://github.com/actions/stale/releases)
- [Changelog](https://github.com/actions/stale/blob/main/CHANGELOG.md)
- [Commits](actions/stale@v4...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>

* Update stale.yml

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Stefanie Molin <24376333+stefmolin@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/stale.yml

@@ -13,7 +13,7 @@ jobs:
   stale:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/stale@v4
+      - uses: actions/stale@28ca1036281a5e5922ead5184a1bbf96e5fc984e  # v9.0.0
         with:
           days-before-stale: 30
           days-before-close: 7