Enable maven caching in setup-java

https://github.blog/changelog/2021-08-30-github-actions-setup-java-now-supports-dependency-caching/

PiperOrigin-RevId: 396943325
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 72b5d6d..a4b86d9 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -52,18 +52,12 @@
           access_token: ${{ github.token }}
       - name: 'Check out repository'
         uses: actions/checkout@v2
-      - name: 'Cache local Maven repository'
-        uses: actions/cache@v2
-        with:
-          path: ~/.m2/repository
-          key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}
-          restore-keys: |
-            ${{ runner.os }}-maven-
       - name: 'Set up JDK ${{ matrix.java }}'
         uses: actions/setup-java@v2
         with:
           java-version: ${{ matrix.java }}
           distribution: 'temurin'
+          cache: 'maven'
       - name: 'Install'
         shell: bash
         run: mvn install -DskipTests=true -Dmaven.javadoc.skip=true -B -V