* Fix alternate lang tags

* prettier

* Scope down the change

---------

Co-authored-by: Dan Abramov <[email protected]>

# Conflicts:
#	beta/package.json
#	beta/src/content/learn/add-react-to-a-website.md
#	beta/src/content/learn/describing-the-ui.md
#	beta/src/content/learn/editor-setup.md
#	beta/src/content/learn/javascript-in-jsx-with-curly-braces.md
#	beta/src/content/learn/react-developer-tools.md
#	beta/src/content/learn/start-a-new-react-project.md
#	beta/src/sidebarLearn.json
#	beta/yarn.lock
#	content/docs/add-react-to-a-website.md
#	content/docs/cdn-links.md
#	content/docs/components-and-props.md
#	content/docs/composition-vs-inheritance.md
#	content/docs/conditional-rendering.md
#	content/docs/create-a-new-react-app.md
#	content/docs/error-boundaries.md
#	content/docs/forms.md
#	content/docs/forwarding-refs.md
#	content/docs/fragments.md
#	content/docs/getting-started.md
#	content/docs/handling-events.md
#	content/docs/hello-world.md
#	content/docs/hooks-custom.md
#	content/docs/hooks-effect.md
#	content/docs/hooks-faq.md
#	content/docs/hooks-intro.md
#	content/docs/hooks-overview.md
#	content/docs/hooks-reference.md
#	content/docs/hooks-state.md
#	content/docs/introducing-jsx.md
#	content/docs/jsx-in-depth.md
#	content/docs/lifting-state-up.md
#	content/docs/lists-and-keys.md
#	content/docs/portals.md
#	content/docs/react-without-es6.md
#	content/docs/react-without-jsx.md
#	content/docs/reconciliation.md
#	content/docs/reference-dom-elements.md
#	content/docs/reference-events.md
#	content/docs/reference-react-component.md
#	content/docs/reference-react-dom-server.md
#	content/docs/reference-react-dom.md
#	content/docs/reference-react.md
#	content/docs/refs-and-the-dom.md
#	content/docs/render-props.md
#	content/docs/rendering-elements.md
#	content/docs/state-and-lifecycle.md
#	content/docs/strict-mode.md
#	content/docs/thinking-in-react.md
#	content/docs/uncontrolled-components.md
#	content/docs/web-components.md
#	content/tutorial/tutorial.md
#	yarn.lock

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