Update android_test.yml

.github/workflows/android_test.yml

@@ -21,6 +21,15 @@ jobs:
         distribution: 'adopt'
     - name: Setup Android SDK
       uses: android-actions/setup-android@v2
+      
+    - uses: actions/cache@v2
+      with:
+        path: |
+            ~/.gradle/caches
+            ~/.gradle/wrapper
+        key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle*', '**/gradle-wrapper.properties') }}
+        restore-keys: |
+            ${{ runner.os }}-gradle-
 
     - name: Grant execute permission for gradlew
       run: chmod +x gradlew