Bump actions/cache from 5.0.5 to 6.1.0

Bumps [actions/cache](https://github.com/actions/cache) from 5.0.5 to 6.1.0.
- [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/v5.0.5...v6.1.0)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-version: 6.1.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/appimage.yml

@@ -69,7 +69,7 @@ jobs:
           git fetch --deepen=15000 --no-recurse-submodules --tags --force upstream || exit 0
 
       - name: Set up ccache for ${{ matrix.id }}
-        uses: actions/cache@v5.0.5
+        uses: actions/cache@v6.1.0
         with:
           path: ${{ env.CCACHE_DIR }}
           key: ${{ runner.os }}-ccache-${{ matrix.id }}-${{ github.sha }}