Bump actions/checkout from 4.1.4 to 4.1.6

Bumps [actions/checkout](https://github.com/actions/checkout) from 4.1.4 to 4.1.6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v4.1.4...v4.1.6)

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

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

.github/workflows/unit_tests.yml

@@ -22,7 +22,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout the repository
-        uses: actions/[email protected].4
+        uses: actions/[email protected].6
 
       - name: Run BATS tests
         uses: ffurrer2/[email protected]