Build: Run storybook in react@17

[shilman]

Issue: #12977

What I did

• Update root package to allow react@17
• Update react-testing-library

How to test

See CI, official-storybook

[ndelangen]

😭

ERROR in /tmp/storybook/lib/components/src/typography/DocumentFormattingSample.md
Module build failed (from /tmp/storybook/node_modules/babel-loader/lib/index.js):
SyntaxError: /tmp/storybook/lib/components/src/typography/DocumentFormattingSample.md: pragma and pragmaFrag cannot be set when runtime is automatic.
> 1 | 
    | ^
  2 | import React from 'react'
  3 | import { mdx } from '@mdx-js/react'
  4 | 
    at File.buildCodeFrameError (/tmp/storybook/node_modules/@babel/core/lib/transformation/file/file.js:250:12)
    at NodePath.buildCodeFrameError (/tmp/storybook/node_modules/@babel/core/node_modules/@babel/traverse/lib/path/index.js:163:21)
    at PluginPass.enter (/tmp/storybook/node_modules/@babel/helper-builder-react-jsx-experimental/lib/index.js:167:26)
    at newFn (/tmp/storybook/node_modules/@babel/core/node_modules/@babel/traverse/lib/visitors.js:175:21)
    at NodePath._call (/tmp/storybook/node_modules/@babel/core/node_modules/@babel/traverse/lib/path/context.js:55:20)
    at NodePath.call (/tmp/storybook/node_modules/@babel/core/node_modules/@babel/traverse/lib/path/context.js:42:17)
    at NodePath.visit (/tmp/storybook/node_modules/@babel/core/node_modules/@babel/traverse/lib/path/context.js:92:31)
    at TraversalContext.visitQueue (/tmp/storybook/node_modules/@babel/core/node_modules/@babel/traverse/lib/context.js:116:16)
    at TraversalContext.visitSingle (/tmp/storybook/node_modules/@babel/core/node_modules/@babel/traverse/lib/context.js:88:19)
    at TraversalContext.visit (/tmp/storybook/node_modules/@babel/core/node_modules/@babel/traverse/lib/context.js:144:19)
    at Function.traverse.node (/tmp/storybook/node_modules/@babel/core/node_modules/@babel/traverse/lib/index.js:82:17)
    at traverse (/tmp/storybook/node_modules/@babel/core/node_modules/@babel/traverse/lib/index.js:64:12)
    at transformFile (/tmp/storybook/node_modules/@babel/core/lib/transformation/index.js:107:29)
    at transformFile.next (<anonymous>)
    at run (/tmp/storybook/node_modules/@babel/core/lib/transformation/index.js:35:12)
    at run.next (<anonymous>)

[shilman]

self-merging @ndelangen -- thanks for the help on this