Fix crash when sending telegram entry help message

src/telegram/telegram.service.ts

@@ -73,7 +73,7 @@ export class TelegramService {
             default:
                 return this.sendError(
                     msg,
-                    'Usage: /entry <private|public|clear>',
+                    'Usage: /entry <private\\|public\\|clear>',
                 );
         }
     }