chore(deps): bump actions/checkout from 3 to 4 (#794)

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]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/dartdoc.yml

@@ -12,7 +12,7 @@ jobs:
         if: github.repository_owner  == 'openfoodfacts'
         steps:
         - name: Checkout code
-          uses: actions/checkout@v3
+          uses: actions/checkout@v4
 
         - name: Setup Dart
           uses: dart-lang/setup-dart@v1

.github/workflows/test-sdk.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Chekout code
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Setup Dart
         uses: dart-lang/setup-dart@v1