minor fix

testing/register-test-core/src/main/java/org/opengroup/osdu/register/subscriber/CreateSubscriberDescriptor.java

@@ -50,7 +50,7 @@ public class CreateSubscriberDescriptor extends RestDescriptor {
         String secret = Config.Instance().SUBSCRIBER_SECRET;
         String topicName = System.getProperty("TEST_TOPIC_NAME", System.getenv("TEST_TOPIC_NAME"));
 
-        if(topicName == null) {
+        if(Strings.isNullOrEmpty(topicName)) {
             topicName = "records-changed";
         }