Update react version to rc in react-18 doc (#32473)

* Update react version to rc in react-18 doc

* Apply suggestions from code review

Co-authored-by: Steven <steven@ceriously.com>
Co-authored-by: Lee Robinson <me@leerob.io>

docs/advanced-features/react-18.md

@@ -2,14 +2,14 @@
 
 [React 18](https://reactjs.org/blog/2021/06/08/the-plan-for-react-18.html) adds new features including, Suspense, automatic batching of updates, APIs like `startTransition`, and a new streaming API for server rendering with support for `React.lazy`.
 
-React 18 is still in beta. Read more about React 18's [release plan](https://github.com/reactwg/react-18/discussions) and discussions from the [working group](https://github.com/reactwg/react-18/discussions).
+React 18 is in RC now. Read more about React 18's [release plan](https://github.com/reactwg/react-18/discussions) and discussions from the [working group](https://github.com/reactwg/react-18/discussions).
 
 ### React 18 Usage in Next.js
 
-Ensure you have the `beta` version of React installed:
+Ensure you have the `rc` npm tag of React installed:
 
 ```jsx
-npm install next@latest react@beta react-dom@beta
+npm install next@latest react@rc react-dom@rc
 ```
 
 ### Enable SSR Streaming (Alpha)