chore(deps): bump actions/cache from 4 to 6 (#4945)

Bumps [actions/cache](https://github.com/actions/cache) from 4 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/v4...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] <support@github.com>
Co-authored-by: Daniel Gibbs <me@danielgibbs.co.uk>
Co-authored-by: unknown <unknown@example.com>
Co-authored-by: LinuxGSM <dev@linuxgsm.com>
Co-authored-by: Knoxed <1338733+knoxed@users.noreply.github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: WildPenguin <ville.aakko@gmail.com>
Co-authored-by: Copilot <copilot@github.com>
Co-authored-by: Jacob Gerega <22921310+jgerega107@users.noreply.github.com>
Co-authored-by: dgibbs64 <dgibbs64@users.noreply.github.com>
Co-authored-by: Nikolay Asenov <10465782+nasenov@users.noreply.github.com>
Co-authored-by: Fabian Raab <fabian@raab.link>
Co-authored-by: yourfate <2371889-youRFate@users.noreply.gitlab.com>
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-authored-by: fwillo <37631375+fwillo@users.noreply.github.com>
Co-authored-by: Silas J. Matson <sjmatson01@gmail.com>

.github/workflows/action-details-check.yml

@@ -100,7 +100,7 @@ jobs:
         run: wget "https://raw.githubusercontent.com/GameServerManagers/LinuxGSM/${LGSM_REF}/linuxgsm.sh"; chmod +x linuxgsm.sh
 
       - name: Cache apt packages
-        uses: actions/cache@v4
+        uses: actions/cache@v6
         with:
           path: /var/cache/apt/archives
           key: apt-${{ runner.os }}-libxml2-utils-jq