[core] Switch to React 17

[eps1lon]

Not particularly fond of having that many peer warnings. Scanned a few of the libraries and nothing stood out. Most likely candidate to break is react-swipeable-view (close to DOM).

Manual checks:

• next workflow green (where we would run nightlies): https://app.circleci.com/pipelines/github/mui-org/material-ui/39485/workflows/b67d9927-a6c8-4d83-b24c-de146b7febeb
• test:karma:profile green:
  • CI: https://app.circleci.com/pipelines/github/mui-org/material-ui/39484/workflows/df8620e1-13dc-4b4d-b787-ff48b0fcae5c/jobs/233468
  • UI: https://mui-dashboard.netlify.app/test-profile/233468
• benchmark azp job green: https://dev.azure.com/mui-org/Material-UI/_build/results?buildId=25217&view=logs&j=ebe19b7c-f100-5cb1-71fb-830731305756

Keeping test branching in place in case we want to run the test suite with 16.

Follow-up (separate PR):

• Drop support of React 16 (peer dependency bump): [core] Drop support for React 16 #25464

Incorrect peer warning:

• @mdx-js/react: v2 alpha supports React 17 (blocked by theme-ui)
• framer: Sent a mail to their support (no github repo for framer found)
• material-ui-popup-state: 1.8.0 (dependabot will solve it)
• react-smooth (required by recharts): refactor: moved to compatible with React 17 recharts/react-smooth#48
• react-swipeable-views: ?
• react-text-mask: Looks unmaintained. See fix peer dependency please for react text-mask/text-mask#1032
• react-virtualized: Update peer dependencies to allow React 17 bvaughn/react-virtualized#1625
• theme-ui: v1 alpha supports React 17

[mui-pr-bot]

No bundle size changes

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