ci: bump actions/cache from 5 to 6 (#8230)

Bumps [actions/cache](https://github.com/actions/cache) from 5 to 6.
- [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...v6)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/uring-kernel-version-test.yml

@@ -25,7 +25,7 @@ jobs:
 
       - name: Cache Linux source
         id: cache-kernel
-        uses: actions/cache@v5
+        uses: actions/cache@v6
         with:
           path: linux-${{ env.KERNEL_VERSION }}
           key: kernel-${{ env.KERNEL_VERSION }}