perf(v2): use @babel/runtime plugin to reduce codesize

[endiliey]

Motivation

Utilize https://babeljs.io/docs/en/babel-plugin-transform-runtime/

WHY ?

Babel uses very small helpers for common functions such as _extend. By default this will be added to every file that requires it. This duplication is sometimes unnecessary, especially when your application is spread out over multiple files.

This is where the @babel/plugin-transform-runtime plugin comes in: all of the helpers will reference the module @babel/runtime to avoid duplication across your compiled output. The runtime will be compiled into your build.

See https://babeljs.io/docs/en/babel-plugin-transform-runtime/#why for more details.

Also checked CRA, Razzle and Gatsby. They are using it too.
See test plan for benefits

Have you read the Contributing Guidelines on pull requests?

yes

Test Plan

Before
Parsed Size: All 1.28mb main 221.62kb

Gzipped Size: All 409.58kb main 69.98kb

After
Parsed Size: All 1.2mb main 206.94kb

Gzipped size: All 399.19kb main 64.63kb

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Deploy preview for docusaurus-preview ready!

Built with commit 75f3fb2

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[yangshun]

Good perf win :)