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] <[email protected]>

.github/workflows/build.yml

@@ -24,7 +24,7 @@ jobs:
       with:
         go-version: ${{ matrix.go }}
     - name: Check out code
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
     - name: Run tests with race detector
       run: go test -mod=readonly -race -tags="libc.memgrind" -v ./...
       if: ${{ matrix.arch == 'amd64' }}
@@ -44,7 +44,7 @@ jobs:
       with:
         go-version: "1.20"
     - name: Check out code
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
     - name: Run tests
       run: go test -mod=readonly -race -v ./...
       working-directory: ./cmd/zombiezen-sqlite-migrate