Update gradle.yml

Author: ZheSun88

.github/workflows/gradle.yml

@@ -19,7 +19,7 @@ jobs:
       with:
         java-version: ${{ matrix.java }}
     - name: Cache Gradle packages
-      uses: actions/cache@v2
+      uses: actions/cache@v4
       with:
         path: |
           ~/.gradle/caches