Clean up warnings

spring-websocket/src/main/java/org/springframework/web/socket/sockjs/frame/Jackson2SockJsMessageCodec.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -71,7 +71,6 @@ public class Jackson2SockJsMessageCodec extends AbstractSockJsMessageCodec {
 	}
 
 	@Override
-	@SuppressWarnings("deprecation")
 	protected char[] applyJsonQuoting(String content) {
 		return JsonStringEncoder.getInstance().quoteAsString(content);
 	}