Bump actions/checkout from 3 to 4

Bumps [actions/checkout](https://github.com/actions/checkout) from 3 to 4.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v3...v4)

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

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/infection.yml

@@ -20,7 +20,7 @@ jobs:
           coverage: "xdebug"
 
       - name: "Checkout code"
-        uses: "actions/checkout@v3"
+        uses: "actions/checkout@v4"
 
       - name: "Fetch Git base reference"
         run: "git fetch --depth=1 origin ${GITHUB_BASE_REF}"