[bug report] execute the command cross env node_ ENV=production webpack --config build/ webpack.extension.js Error: This [module]_ TYPE] is not a function

### Element UI version
2.15.1

### OS/Browsers version
windows10 /

### Vue version
2.6.12

### Reproduction Link
https://elementui.github.io/issue-generator/#/zh-CN

### Steps to reproduce
element-dev 执行命令cross-env NODE_ENV=production webpack --config build/webpack.extension.js

### What is Expected?
执行命令cross-env NODE_ENV=production webpack --config build/webpack.extension.js 不会报错

### What is actually happening?
执行命令cross-env NODE_ENV=production webpack --config build/webpack.extension.js 报错：this[MODULE_TYPE] is not a function