refactor: 삭제된 기능 테스트 부분 삭제

Author: audwls239

NBE_5_7_2_02TEAM/src/test/java/io/twogether/nbe_5_7_2_02team/chat/service/ChatMemberServiceTest.java

@@ -197,19 +197,6 @@ void createChatMemberNoChatRoomTest() {
         assertEquals(CHAT_ROOM_NOT_FOUND, errorException.getErrorCode());
     }
 
-    @Test
-    @DisplayName("채팅방 입장 테스트: 에러 - 이미 참여중")
-    void createChatMemberAlreadyJoinTest() {
-        chatMemberService.createChatMember(chatRoomId, userDetails1);
-
-        ErrorException errorException =
-                assertThrows(
-                        ErrorException.class,
-                        () -> chatMemberService.createChatMember(chatRoomId, userDetails1));
-
-        assertEquals(CHAT_MEMBER_ALREADY_EXISTS, errorException.getErrorCode());
-    }
-
     @Test
     @DisplayName("멤버 상태 변경 테스트: 성공")
     void updateChatMemberTest() {