chore: update import statements to esm

[sergeycw]

Description

All import statements in documentation and internal code changed from import React from 'react' to import * as React from 'react'

Documentation

Related Issues

Fixes #21697

[KyleAMathews]

@sergeycw looks like there's some test failures — could you look into this?

[wardpeet]

Thanks @sergeycw this looks great!

I've tested this on the earliest react version and 👍

[gatsbot]

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