Bump actions/checkout from 4 to 6 (#11547)

Bumps [actions/checkout](https://github.com/actions/checkout) from 4 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](https://github.com/actions/checkout/compare/v4...v6)

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

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

.github/workflows/build_all.yml

@@ -84,7 +84,7 @@ jobs:
     if: ${{ !cancelled() && success() }}
     steps:
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           sparse-checkout: |
             .github
@@ -145,7 +145,7 @@ jobs:
     - name: "Remove unneeded stuff to free disk space"
       run:
         rm -rf /usr/local/lib/android/* /usr/share/dotnet/* /opt/ghc1/* "/usr/local/share/boost1/*" /opt/hostedtoolcache1/*
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Get the version and date
       run: |
         ver_pure=$(grep 'set(SoftFever_VERSION' version.inc | cut -d '"' -f2)