Fix deprecated usage of gradle-build action

.forgejo/workflows/pull_request.yml

@@ -55,10 +55,10 @@ jobs:
           java-version: '17'
       - name: Setup Android SDK
         uses: https://git.wbrawner.com/android-actions/setup-android@v3
-      - name: Build with Gradle
-        uses: https://git.wbrawner.com/gradle/gradle-build-action@v3
-        with:
-          arguments: assemblePlayDebug assemblePlayDebugAndroidTest
+      - name: Setup Gradle
+        uses: https://git.wbrawner.com/gradle/actions/setup-gradle@v4
+      - name: Build APKs
+        run: ./gradlew assemblePlayDebug assemblePlayDebugAndroidTest
       - name: Grant execute permission for flank_auth.sh
         run: chmod +x flank_auth.sh
       - name: Add auth for flank
@@ -67,6 +67,4 @@ jobs:
         run: |
           ./flank_auth.sh
       - name: Run UI tests
-        uses: https://git.wbrawner.com/gradle/gradle-build-action@v3
-        with:
-          arguments: runFlank
+        run: ./gradlew runFlank