ci: Bump actions/checkout from 4.1.5 to 4.1.6

Bumps [actions/checkout](https://github.com/actions/checkout) from 4.1.5 to 4.1.6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@44c2b7a...a5ac7e5)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/rust.yml

@@ -16,7 +16,7 @@ jobs:
     runs-on: ubuntu-22.04
 
     steps:
-      - uses: actions/checkout@44c2b7a8a4ea60a981eaca3cf939b5f4305c123b
+      - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29
       - name: Build
         run: cargo build --verbose
       - name: Format