fix: 把inviter改为string类型

src/modules/user/user.controller.js

@@ -1,13 +1,11 @@
 const User = require('./user.model');
 const MsgCode = require('../msgCode/msgCode.controller');
 const changePwd = require('../sign/sign.controller').changePasswd;
-const mongoose = require('mongoose');
 
 module.exports = {
     changePwd,
     async createNewUser (data) {
         let { phone, inviter, password } = data;
-        if (inviter) inviter = new mongoose.Types.ObjectId(inviter);
         await (new User({ phone, inviter, password })).save().then(user => user).catch(err => {
             mylog.error('创建新用户失败', err);
             return null;