Bump actions/checkout from 6 to 7

Bumps [actions/checkout](https://github.com/actions/checkout) from 6 to 7.
- [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/v6...v7)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/docker-3.3dev.yml

@@ -22,7 +22,7 @@ jobs:
         run: echo "REPO=${GITHUB_REPOSITORY@L}" >> "${GITHUB_ENV}"
 
       - name: Source checkout
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
 
       - name: Setup QEMU
         id: qemu