Setting @vue/babel-preset-app useBuiltsIn to false results in corejs warnings

[LeBenLeBen]

Version

4.2.3

Reproduction link

https://github.com/LeBenLeBen/vue-cli-usebuiltins-corejs

Environment info

  System:
    OS: macOS 10.15.3
    CPU: (12) x64 Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz
  Binaries:
    Node: 12.14.0 - ~/.nvm/versions/node/v12.14.0/bin/node
    Yarn: 1.21.1 - ~/.nvm/versions/node/v12.14.0/bin/yarn
    npm: 6.13.6 - ~/.nvm/versions/node/v12.14.0/bin/npm
  Browsers:
    Chrome: 80.0.3987.122
    Firefox: 73.0.1
    Safari: 13.0.5
  npmPackages:
    @egoist/vue-to-react: ^1.1.0 => 1.1.0
    @storybook/vue: ^5.3.14 => 5.3.14
    @vue/babel-helper-vue-jsx-merge-props:  1.0.0
    @vue/babel-plugin-transform-vue-jsx:  1.1.2
    @vue/babel-preset-app:  4.2.3
    @vue/babel-preset-jsx:  1.1.2
    @vue/babel-sugar-functional-vue:  1.1.2
    @vue/babel-sugar-inject-h:  1.1.2
    @vue/babel-sugar-v-model:  1.1.2
    @vue/babel-sugar-v-on:  1.1.2
    @vue/cli-overlay:  4.2.3
    @vue/cli-plugin-babel: ~4.2.3 => 4.2.3
    @vue/cli-plugin-eslint: ~4.2.3 => 4.2.3
    @vue/cli-plugin-router:  4.2.3
    @vue/cli-plugin-typescript: ~4.2.3 => 4.2.3
    @vue/cli-plugin-unit-jest: ~4.2.3 => 4.2.3
    @vue/cli-plugin-vuex:  4.2.3
    @vue/cli-service: ~4.2.3 => 4.2.3
    @vue/cli-shared-utils:  4.2.3
    @vue/component-compiler-utils:  3.1.1
    @vue/eslint-config-prettier: ^6.0.0 => 6.0.0
    @vue/eslint-config-typescript: ^5.0.2 => 5.0.2
    @vue/preload-webpack-plugin:  1.1.1
    @vue/test-utils: 1.0.0-beta.31 => 1.0.0-beta.31
    @vue/web-component-wrapper:  1.2.0
    eslint-plugin-vue: ^6.2.1 => 6.2.1
    jest-serializer-vue:  2.0.2
    typescript: ~3.8.3 => 3.8.3
    vue: ^2.6.11 => 2.6.11
    vue-cli-plugin-storybook: ~1.2.1 => 1.2.1
    vue-cli-plugin-tailwind: ~1.2.0 => 1.2.0
    vue-docgen-api:  4.12.0
    vue-docgen-loader:  1.5.0
    vue-eslint-parser:  7.0.0
    vue-functional-data-merge: ^3.1.0 => 3.1.0
    vue-hot-reload-api:  2.3.4
    vue-jest:  3.0.5
    vue-loader:  15.9.0
    vue-style-loader:  4.1.2
    vue-template-compiler: ^2.6.11 => 2.6.11
    vue-template-es2015-compiler:  1.9.1
  npmGlobalPackages:
    @vue/cli: 4.2.2

Steps to reproduce

1. Clone the repository
2. Install dependencies
3. Run either npm run serve or npm run build

What is expected?

No warning should be emitted from Babel preset env.

What is actually happening?

Babel emit the following warning message:

The corejs option only has an effect when the useBuiltIns option is not false

---

This is not really bothering in a default Vue CLI environment where the log is cleared frequently, but when working on or building a Storybook instance for example it throws this warning many times.