Polish Javadoc for messaging annotations

spring-messaging/src/main/java/org/springframework/messaging/handler/annotation/MessageMapping.java

@@ -26,7 +26,7 @@ import org.springframework.messaging.Message;
 
 
 /**
- * Annotation for mapping a {@link Message} onto specific handler handler methods based on
+ * Annotation for mapping a {@link Message} onto specific handler methods based on
  * the destination for the message.
  *
  * @author Rossen Stoyanchev

spring-messaging/src/main/java/org/springframework/messaging/simp/annotation/SubscribeEvent.java

@@ -24,7 +24,7 @@ import java.lang.annotation.Target;
 
 
 /**
- * Annotation for mapping subscription events onto specific handler handler methods based
+ * Annotation for mapping subscription events onto specific handler methods based
  * on the destination for the message (e.g. STOMP SUBSCRIBE message).
  *
  * @author Rossen Stoyanchev

spring-messaging/src/main/java/org/springframework/messaging/simp/annotation/UnsubscribeEvent.java

@@ -24,7 +24,7 @@ import java.lang.annotation.Target;
 
 
 /**
- * Annotation for mapping unsubscribe events onto specific handler handler methods based
+ * Annotation for mapping unsubscribe events onto specific handler methods based
  * on the destination for the message (e.g. STOMP UNSUBSCRIBE message).
  *
  * @author Rossen Stoyanchev