[Bug Report] vite build error vite build vue2 element-ui@2.15.12 'addClass' is not exported by node_modules

### Element UI version
2.15.12

### OS/Browsers version
mac

### Vue version
2.6.11

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

### Steps to reproduce
vite build

### What is Expected?
build pass

### What is actually happening?
'addClass' is not exported by ../node_modules/.pnpm/element-ui@2.15.12_vue@2.6.11/node_modules/element-ui/lib/utils/dom.js, imported by ../node_modules/.pnpm/element-ui@2.15.12_vue@2.6.11/node_modules/element-ui/lib/utils/popup/popup-manager.js

if version element-ui@2.15.10
Error: 'default' is not exported by ../node_modules/.pnpm/@element-ui@1.0.1/node_modules/@tj/element-ui/lib/index.js