Bump actions/checkout from 3 to 4 (#163)

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

.github/workflows/ci-dev.yml

@@ -27,7 +27,7 @@ jobs:
       cancel-in-progress: true
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - uses: coq-community/docker-coq-action@v1
       with:
         coq_version: ${{ matrix.coq-version }}

.github/workflows/ci.yml

@@ -39,7 +39,7 @@ jobs:
         sudo add-apt-repository "$PPA" -y
         sudo apt-get -o Acquire::Retries=30 update -q
         sudo apt-get -o Acquire::Retries=30 install $COQ_PACKAGE -y --allow-unauthenticated
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v4
       with: