chore(deps): bump actions/checkout from 3 to 4 (#172)

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>
Co-authored-by: Oleksandr Prokhorenko <[email protected]>

Author: dependabot[bot]

.github/workflows/flutter-mobile-integration-test.yml

@@ -20,7 +20,7 @@ jobs:
     timeout-minutes: 30
     steps:
       - name: ⬇️ Checkout repository
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: ⤵️ Authenticate with Google Cloud Platform
         uses: "google-github-actions/auth@v2"

.github/workflows/flutter-web-integration-test.yml

@@ -28,7 +28,7 @@ jobs:
     timeout-minutes: 30
     steps:
       - name: ⬇️ Checkout repository
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: ⚙️ Setup Flutter
         uses: subosito/flutter-action@v2