Use spring-javaformat to format and check code

Resolves: #1450

spring-session-samples/spring-session-sample-boot-websocket/src/main/java/sample/data/User.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2017 the original author or authors.
+ * Copyright 2014-2019 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.
@@ -111,4 +111,5 @@ public class User implements Serializable {
 	}
 
 	private static final long serialVersionUID = 2738859149330833739L;
+
 }