add github action

.github/workflows/android-unit-test.yml

@@ -0,0 +1,33 @@
+name: Android Unit Test
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Set up JDK 8
+        uses: actions/setup-java@v2
+        with:
+          distribution: 'adopt'
+          java-version: '8'
+
+      - name: Grant execute permission for gradlew
+        run: chmod +x gradlew
+
+      - name: Build and run unit tests
+        run: ./gradlew testDebug
+
+      - name: Upload test results
+        uses: actions/upload-artifact@v2
+        with:
+          name: test-results
+          path: app/build/test-results