fix topic level

DOCUMENTATION.md

@@ -1267,20 +1267,20 @@ Available types:
 
 Default: `none`
 
-#### rabbitmq_endpoint
+##### rabbitmq_endpoint
 
 End-point address for rabbitmq server.
 Ex: amqp://user:password@localhost:5672/
 
 Default:
 
-#### rabbitmq_topic
+##### rabbitmq_topic
 
 RabbitMQ topic to publish message.
 
 Default:
 
-#### rabbitmq_queue_type
+##### rabbitmq_queue_type
 
 RabbitMQ queue type for the topic.