Update actions/checkout action to v3 (#28)

Co-authored-by: Renovate Bot <[email protected]>

Author: renovate[bot]

.github/workflows/test.yml

@@ -7,6 +7,6 @@ jobs:
     runs-on: macos-latest
 
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Run unit tests
       run: ./gradlew app:test