Bump actions/checkout from 2 to 4

Bumps [actions/checkout](https://github.com/actions/checkout) from 2 to 4.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v2...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

@@ -45,7 +45,7 @@ jobs:
             rust: stable
             target: x86_64-pc-windows-msvc
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
       - name: Install Rust (rustup)
         run: rustup update ${{ matrix.rust }} --no-self-update && rustup default ${{ matrix.rust }}
         shell: bash