Bump actions/cache from 3.0.7 to 3.0.8

Bumps [actions/cache](https://github.com/actions/cache) from 3.0.7 to 3.0.8.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](https://github.com/actions/cache/compare/v3.0.7...v3.0.8)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

.github/workflows/appcast.yml

@@ -15,7 +15,7 @@ jobs:
         persist-credentials: false
 
     - name: Cache 📦
-      uses: actions/cache@v3.0.7
+      uses: actions/cache@v3.0.8
       with:
         path: AppCast/vendor/bundle
         key: ${{ runner.os }}-gems-v1.0-${{ hashFiles('AppCast/Gemfile') }}