Merge remote-tracking branch 'origin/feat/20' into feat/20

# Conflicts:
#	backend/src/main/java/io/f1/backend/domain/game/app/RoomService.java
#	backend/src/test/java/io/f1/backend/domain/game/app/RoomServiceTests.java

Author: sehee123

backend/src/main/java/io/f1/backend/domain/game/model/Room.java

@@ -27,7 +27,7 @@ public class Room {
 
     private Map<String, Player> playerSessionMap = new ConcurrentHashMap<>();
 
-    private Map<Long,String> userIdSessionMap = new ConcurrentHashMap<>();
+    private Map<Long, String> userIdSessionMap = new ConcurrentHashMap<>();
 
     private final LocalDateTime createdAt = LocalDateTime.now();
 
@@ -36,7 +36,6 @@ public Room(Long id, RoomSetting roomSetting, GameSetting gameSetting, Player ho
         this.roomSetting = roomSetting;
         this.gameSetting = gameSetting;
         this.host = host;
-
     }
 
     public boolean isHost(Long id){

backend/src/main/java/io/f1/backend/domain/game/websocket/GameSocketController.java

@@ -25,7 +25,8 @@ public void initializeRoomSocket(@DestinationVariable Long roomId, Message<?> me
 
         String websocketSessionId = getSessionId(message);
 
-        RoomInitialData roomInitialData = roomService.initializeRoomSocket(roomId, websocketSessionId);
+        RoomInitialData roomInitialData =
+                roomService.initializeRoomSocket(roomId, websocketSessionId);
         String destination = roomInitialData.destination();
 
         messageSender.send(