⬆ Bump actions/checkout from 3 to 4 (#670)

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](https://github.com/actions/checkout/compare/v3...v4)

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

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

.github/workflows/build-docs.yml

@@ -17,7 +17,7 @@ jobs:
     outputs:
       docs: ${{ steps.filter.outputs.docs }}
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     # For pull requests it's not necessary to checkout the code but for the main branch it is
     - uses: dorny/paths-filter@v2
       id: filter
@@ -41,7 +41,7 @@ jobs:
         env:
           GITHUB_CONTEXT: ${{ toJson(github) }}
         run: echo "$GITHUB_CONTEXT"
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Set up Python
         uses: actions/setup-python@v4
         with: