message: [Be] Fix MessagesServiceTest, waiting of kafka write added
diff: @@ -61,12 +61,12 @@ class MessagesServiceTest extends AbstractIntegrationTest {
  }
  @Test
  - void maskingAppliedOnConfiguredClusters() {
  + void maskingAppliedOnConfiguredClusters() throws Exception {
  String testTopic = MASKED_TOPICS_PREFIX + UUID.randomUUID();
  try (var producer = KafkaTestProducer.forKafka(kafka)) {
  createTopic(new NewTopic(testTopic, 1, (short) 1));
  producer.send(testTopic, "message1");
  - producer.send(testTopic, "message2");
  + producer.send(testTopic, "message2").get();
  Flux<TopicMessageDTO> msgsFlux = messagesService.loadMessages(
  cluster,
  