Switch to caching Gradle wrapper and components (#3348)

Adds a cache for Gradle components. Cache will be saved on successful
build and keyed off Android gradle build files.

b/337337924

(cherry picked from commit 9b5edf1)

.github/workflows/main.yaml

@@ -239,12 +239,21 @@ jobs:
           # Use fetch depth of 0 to get full history for a valid build id.
           fetch-depth: 0
           persist-credentials: false
-      - name: Setup Gradle
+      - name: Cache Gradle
+        uses: actions/cache@v3
         if: startsWith( matrix.target_platform , 'android')
+<<<<<<< HEAD
         run: |
           for i in `seq 1 5`; do
             starboard/android/apk/gradlew --version || true
           done
+=======
+        with:
+          key: gradle-cache-${{ hashFiles('starboard/android/apk/**/*gradle*') }}
+          path: |
+            /root/.gradle/caches
+            /root/.gradle/wrapper
+>>>>>>> 9b5edf1729a (Switch to caching Gradle wrapper and components (#3348))
       - name: GN
         uses: ./.github/actions/gn
       - name: Build Cobalt