Bump cirrus-actions/rebase from 1.3.1 to 1.8

Bumps [cirrus-actions/rebase](https://github.com/cirrus-actions/rebase) from 1.3.1 to 1.8.
- [Release notes](https://github.com/cirrus-actions/rebase/releases)
- [Commits](https://github.com/cirrus-actions/rebase/compare/1.3.1...1.8)

---
updated-dependencies:
- dependency-name: cirrus-actions/rebase
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

.github/workflows/rebase.yml

@@ -13,6 +13,6 @@ jobs:
       with:
         fetch-depth: 0
     - name: Automatic Rebase
-      uses: cirrus-actions/rebase@1.3.1
+      uses: cirrus-actions/rebase@1.8
       env:
         GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}