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] <support@github.com>

.github/workflows/ci.yml

@@ -18,7 +18,7 @@ jobs:
  os: [ubuntu-latest, macOS-latest, windows-latest]
 
  steps:
- - uses: actions/checkout@v3
+ - uses: actions/checkout@v4
  - name: Set up Python ${{ matrix.python-version }}
  uses: actions/setup-python@v3
  with:
@@ -50,7 +50,7 @@ jobs:
  os: [ ubuntu-latest ]
 
  steps:
- - uses: actions/checkout@v3
+ - uses: actions/checkout@v4
  - name: Set up Python ${{ matrix.python-version }}
  uses: actions/setup-python@v3
  with: