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](actions/cache@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] <support@github.com>

Author: dependabot[bot]

.github/workflows/demo-production-deploy.yml

@@ -72,7 +72,7 @@ jobs:
       with:
         ruby-version: '3.3'
         bundler-cache: true
-    - uses: actions/cache@v5.0.5
+    - uses: actions/cache@v6.1.0
       with:
         path: demo/gemfiles/vendor/bundle
         key: gems-build-kuby-main-ruby-3.3.x-${{ hashFiles('demo/gemfiles/kuby.gemfile.lock') }}