refactor: 이름 변 ChatServer -> ChatServerWebSocket (#12)

Author: mac

…main/java/chat/webSocket/ChatServer.java …/chat/webSocket/ChatServerWebSocket.javasrc/main/java/chat/webSocket/ChatServer.java renamed to src/main/java/chat/webSocket/ChatServerWebSocket.java src/main/java/chat/webSocket/ChatServer.java renamed to src/main/java/chat/webSocket/ChatServerWebSocket.java

@@ -8,7 +8,7 @@
 import java.util.concurrent.CopyOnWriteArraySet;
 
 @ServerEndpoint("/ws/room/{roomId}")
-public class ChatServer {
+public class ChatServerWebSocket {
 
     // roomId -> sessions
     private static final ConcurrentHashMap<String, CopyOnWriteArraySet<Session>> rooms = new ConcurrentHashMap<>();