return error on failure to subscribe to a topic

Change-Id: Iee35d7be2e796f1490cb6c27568dbfc63e46da34
diff --git a/kafka/kafka_inter_container_library.go b/kafka/kafka_inter_container_library.go
index afad2ac..56b5fa1 100644
--- a/kafka/kafka_inter_container_library.go
+++ b/kafka/kafka_inter_container_library.go
@@ -327,6 +327,7 @@
 	if ch, err = kp.kafkaClient.Subscribe(&topic); err != nil {
 		//if ch, err = kp.Subscribe(topic); err != nil {
 		log.Errorw("failed-to-subscribe", log.Fields{"error": err, "topic": topic.Name})
+		return err
 	}
 
 	kp.defaultRequestHandlerInterface = handler