chore(deps): bump actions/cache from 4 to 5

Bumps [actions/cache](https://github.com/actions/cache) from 4 to 5.
- [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/v4...v5)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-version: '5'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

.github/workflows/ci.yml

@@ -221,7 +221,7 @@ jobs:
         with:
           name: webview-resources
           path: App/Resources/webview/
-      # actions/cache@v4 restores the package's `.build/` and SwiftPM's
+      # actions/cache@v5 restores the package's `.build/` and SwiftPM's
       # global cache. On github-hosted this is a real perf win; on self-hosted
       # it's both unnecessary (the _work/ dir persists between jobs naturally)
       # and actively harmful (caches saved on github-hosted have absolute
@@ -231,7 +231,7 @@ jobs:
       # the cache action to github-hosted only.
       - name: Cache SPM build artifacts (github-hosted only)
         if: runner.environment == 'github-hosted'
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: |
             packages/${{ matrix.package }}/.build