[Bug report] @mpx/cli 3.x 分包无效

[naifen00]

问题描述
升级3.0 分包无效

环境信息描述
至少包含以下部分：

   "@mpxjs/api-proxy": "^2.8.0",
   "@mpxjs/core": "^2.8.0",
   "@mpxjs/fetch": "^2.8.0",
   "@mpxjs/pinia": "^2.8.0",
   "@mpxjs/store": "^2.8.0",
   "@mpxjs/utils": "^2.8.0",
   "@mpxjs/babel-plugin-inject-page-events": "^2.8.0",
   "@mpxjs/mpx-cli-service": "^2.0.0",
   "@mpxjs/size-report": "^2.8.0",
   "@mpxjs/vue-cli-plugin-mpx": "^2.0.0",
   "@mpxjs/vue-cli-plugin-mpx-eslint": "^2.0.0",
   "@mpxjs/webpack-plugin": "^2.8.0",

最简复现demo