Update gradle.yml

updated action cache to v4

Author: MehVahdJukaar

.github/workflows/gradle.yml

@@ -13,7 +13,7 @@ jobs:
     - name: Validate gradlew integrity
       uses: gradle/wrapper-validation-action@v1
     - name: Cache
-      uses: actions/cache@v2
+      uses: actions/cache@v4
       with:
         path: |
           ~/.gradle/caches