Bump actions/checkout from 4 to 6 (#27)

Bumps [actions/checkout](https://github.com/actions/checkout) from 4 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v4...v6)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '6'
  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>

Author: dependabot[bot]

.github/workflows/publish-rust-crates-io-v1.yml

@@ -20,7 +20,7 @@ jobs:
       contents: read
     steps:
       - name: Checkout repository contents
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Uninstall existing Rust toolchain (workaround for some runner images)
         run: rustup toolchain uninstall stable