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](actions/cache@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] <[email protected]>

Author: dependabot[bot]

.github/workflows/maven.yaml

@@ -55,7 +55,7 @@ jobs:
 
       - name: restore test times cache if it exists
         id: restore_test_times_cache
-        uses: actions/cache/restore@v4
+        uses: actions/cache/restore@v5
         with:
           path: /tmp/sorted.txt
           key: ${{ runner.os }}-spring-cloud-k8s-existing-test-times-cache-${{ github.run_id }}