Update WebSocketConfig.java

AbstractWebSocketMessageBrokerConfigurer is deprecated in favor of simply using WebSocketMessageBrokerConfigurer

Author: kamelromdhani

src/main/java/com/techprimers/springbootwebsocketexample/config/WebSocketConfig.java

@@ -2,13 +2,13 @@
 
 import org.springframework.context.annotation.Configuration;
 import org.springframework.messaging.simp.config.MessageBrokerRegistry;
-import org.springframework.web.socket.config.annotation.AbstractWebSocketMessageBrokerConfigurer;
+import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer;
 import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker;
 import org.springframework.web.socket.config.annotation.StompEndpointRegistry;
 
 @Configuration
 @EnableWebSocketMessageBroker
-public class WebSocketConfig extends AbstractWebSocketMessageBrokerConfigurer {
+public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {
     @Override
     public void registerStompEndpoints(StompEndpointRegistry stompEndpointRegistry) {
         stompEndpointRegistry.addEndpoint("/websocket-example")