chore(deps): Bump actions/checkout in /.github/actions/prepare-source (…

…#5960)

Bumps [actions/checkout](https://github.com/actions/checkout) from 4.2.1 to 4.2.2.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v4.2.1...v4.2.2)

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

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

.github/actions/prepare-source/action.yml

@@ -4,7 +4,7 @@ runs:
   using: composite
   steps:
     - name: Check out mu-plugins-ext
-      uses: actions/checkout@v4.2.1
+      uses: actions/checkout@v4.2.2
       with:
         repository: 'Automattic/vip-go-mu-plugins-ext'
         path: 'vip-go-mu-plugins-ext'