Bump actions/checkout from 3.6.0 to 4.0.0

Bumps [actions/checkout](https://github.com/actions/checkout) from 3.6.0 to 4.0.0.
- [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/v3.6.0...v4.0.0)

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

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

.github/workflows/sync-back-to-dev.yml

@@ -33,7 +33,7 @@ jobs:
     name: Syncing branches
     steps:
       - name: Checkout
-        uses: actions/checkout@v3.6.0
+        uses: actions/checkout@v4.0.0
       - name: Opening pull request
         run: gh pr create -B development -H master --title 'Sync master back into development' --body 'Created by Github action' --label 'internal'
         env: