Bump GH action for gradle to v4

Author: slinkydeveloper

.github/workflows/integration.yaml

@@ -101,7 +101,7 @@ jobs:
           java-version: '21'
 
       - name: Setup Gradle
-        uses: gradle/actions/setup-gradle@v3
+        uses: gradle/actions/setup-gradle@v4
 
       - name: Build restatedev/test-services-java image
         run: ./gradlew -Djib.console=plain :test-services:jibDockerBuild

.github/workflows/tests.yml

@@ -25,10 +25,7 @@ jobs:
           distribution: 'adopt'
 
       - name: Setup Gradle
-        uses: gradle/actions/setup-gradle@v3
-
-      - name: Validate Gradle wrapper
-        uses: gradle/actions/wrapper-validation@v3
+        uses: gradle/actions/setup-gradle@v4
 
       - name: Pull Restate docker image
         run: docker pull ghcr.io/restatedev/restate:main
@@ -56,7 +53,7 @@ jobs:
           distribution: 'temurin'
           java-version: '21'
       - name: Setup Gradle
-        uses: gradle/actions/setup-gradle@v3
+        uses: gradle/actions/setup-gradle@v4
 
       - name: Build Javadocs
         run: gradle :sdk-aggregated-javadocs:javadoc