Bump actions/checkout from 6.0.2 to 7.0.0

Bumps [actions/checkout](https://github.com/actions/checkout) from 6.0.2 to 7.0.0.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@de0fac2...9c091bb)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: 7.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/build.yaml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0
       - uses: dart-lang/setup-dart@65eb853c7ba17dde3be364c3d2858773e7144260
 
       - name: Install dependencies