React: Upgrade babel-plugin-react-docgen to 4.0.0

[shilman]

Issue: N/A

What I did

How to test

See Docs pages for React sample apps:

• official-storybook
• cra-*

[vercel]

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[patricklafrance]

Here's what I have so far.

I only tested with PropTypes... none of our bugs have been fixed but I can't find any regression... So far so good.

• All addon-docs 302 Jest tests passed
• React.forwardRef & React.memo still doesn't seems to work. Was not working before either.
• Storybook Official props table for PropTypes looks fine.
• cra-ts-kitchen-sink
  -> JSDoc still works
  -> All prop types still works
  -> react-docgen still doesn't support spreaded defaultProps
  -> react-docgen still doesn't support imported object
  -> react-docgen still doesn't respect the props original sort order. Props will a default value are still always first