the TestUtil should be a final class with a private default constructor

Author: ThoSap

operator/src/test/java/it/aboutbits/postgresql/_support/testdata/base/TestUtil.java

@@ -15,7 +15,7 @@
 import static org.awaitility.Awaitility.await;
 
 @NullMarked
-public class TestUtil {
+public final class TestUtil {
     public static void resetEnvironment(KubernetesClient kubernetesClient) {
         // Reverse Dependency Deletion
         deleteResource(kubernetesClient, DefaultPrivilege.class);
@@ -38,4 +38,7 @@ public static void deleteResource(
                 .pollInterval(100, TimeUnit.MILLISECONDS)
                 .until(() -> kubernetesClient.resources(resourceClass).list().getItems().isEmpty());
     }
+
+    private TestUtil() {
+    }
 }