Bump actions/checkout from 3 to 4 (#70)

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

.github/workflows/ci.yaml

@@ -11,7 +11,7 @@ jobs:
         rust: [stable]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: actions/cache@v3
         # https://github.com/actions/cache/blob/main/examples.md#rust---cargo
         with:

.github/workflows/publish.yaml

@@ -10,6 +10,6 @@ jobs:
     if: github.repository_owner == 'Traverse-Research'
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Publish
         run: cargo publish --token ${{ secrets.cratesio_token }}