[bug report] vue-cli @ 3 official document configuration on demand reference, babel-plugin-component needs to be reinstalled to load successfully

### Element UI version
2.13.0

### OS/Browsers version
window10/ 76.0.3809.132 （64 位）

### Vue version
2.6.11

### Reproduction Link
https://github.com/menghuanCode/element-issue

### Steps to reproduce
1. vue create . (create a project)
使用 Vue-cli@3 创建一个项目
2. npm install element-ui
3. npm install babel-plugin-component -D
4. update babel.config.js

```js
module.exports = {
presets: [ '@vue/cli-plugin-babel/preset' ],
plugins: [
[ "component",
{
"libraryName": "element-ui",
"styleLibraryName": "theme-chalk"
}
]
]
}
```

### What is Expected?
Run successfully
运行成功

### What is actually happening?
```txt
ERROR Failed：
This dependency was not found:
* core-js/modules/es.object.to-string in ./src/router/index.js
To install it, you can run: npm install --save core-js/modules/es.object.to-string
```

Need to reinstall babel-plugin-component to run successfully
(需要重新安装 babel-plugin-component 才能运行成功)

I don't know what happened during this time
(我不知道这段时间发生了什么)

I konw vue-cli-plugin-element can use
(我知道有 vue-cli-plugin-element 可以使用)

I am out of curiosity
我出于好奇