[웹소켓] 번역 - line270 (#1606)

Author: Jeehay28

5-network/11-websocket/article.md

@@ -267,7 +267,7 @@ To get connection state, additionally there's `socket.readyState` property with
 
 - **`0`** -- "CONNECTING": the connection has not yet been established,
 - **`1`** -- "OPEN": 연결이 성립되고 통신 중
-- **`2`** -- "CLOSING": the connection is closing,
+- **`2`** -- "CLOSING": 커넥션 종료 중
 - **`3`** -- "CLOSED": 커넥션이 종료됨