chore(deps): update actions/checkout action to v4 (#9)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/release.yml

@@ -11,7 +11,7 @@ jobs:
     name: Package and Publish
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           token: ${{ secrets.REPO_DEPLOYMENT_TOKEN }}
       - uses: dart-lang/setup-dart@v1

.github/workflows/test.yml

@@ -11,7 +11,7 @@ jobs:
     name: Linting and Testing
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: dart-lang/setup-dart@v1
         with:
           sdk: stable