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/desktop-build.yml

@@ -384,7 +384,7 @@ jobs:
       - name: Restore thin Qt ${{ steps.resolve_qt_version.outputs.version }} libraries (${{ matrix.soc }} macOS)
         if: matrix.os == 'macOS'
         id: restore_qt
-        uses: actions/cache/restore@v4
+        uses: actions/cache/restore@v5
         with:
           path: ${{ github.workspace }}/Qt
           key: thin-qt-macos-${{ matrix.soc }}-${{ steps.resolve_qt_version.outputs.version }}
@@ -407,7 +407,7 @@ jobs:
 
       - name: Cache thin Qt libraries (${{ matrix.soc }} macOS)
         if: matrix.os == 'macOS' && steps.restore_qt.outputs.cache-hit != 'true'
-        uses: actions/cache/save@v4
+        uses: actions/cache/save@v5
         with:
           path: ${{ github.workspace }}/Qt
           key: thin-qt-macos-${{ matrix.soc }}-${{ steps.resolve_qt_version.outputs.version }}