ci: 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/build_examples_platformio.yaml

@@ -124,7 +124,7 @@ jobs:
           pip install --upgrade platformio
 
       - name: Restore or Cache PlatformIO Platforms and Libraries
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         id: cache_pio
         with:
           path: ~/.platformio