refactor : add concept module

src/app.module.ts

@@ -9,12 +9,12 @@ import { Game } from './games/entities/game.entity';
 import { Topic } from './word/entities/topic.entity';
 import { Word } from './word/entities/word.entity';
 import { Player } from './games/entities/player.entity';
-import { Concept } from './games/entities/concept.entity';
 import { ConceptInTurn } from './games/entities/concept_in_turn.entity';
 import { ConfigService } from '@nestjs/config';
 import { WordModule } from './word/words.module';
 import { Message } from './games/entities/message.entity';
 import { LobbyModule } from './lobby/lobby.module';
+import { Concept } from './concept/entities/concept.entity';
 
 const configService = new ConfigService();