fix: move hr outside intro

Author: CarreraPHP

src/content/blog/2021/06/08/the-plan-for-react-18.md

@@ -19,10 +19,10 @@ The React team is excited to share a few updates:
 
 These updates are primarily aimed at maintainers of third-party libraries. If you’re learning, teaching, or using React to build user-facing applications, you can safely ignore this post. But you are welcome to follow the discussions in the React 18 Working Group if you're curious!
 
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 </Intro>
 
+---
+
 ## What’s coming in React 18 {/*whats-coming-in-react-18*/}
 
 When it’s released, React 18 will include out-of-the-box improvements (like [automatic batching](https://github.com/reactwg/react-18/discussions/21)), new APIs (like [`startTransition`](https://github.com/reactwg/react-18/discussions/41)), and a [new streaming server renderer](https://github.com/reactwg/react-18/discussions/37) with built-in support for `React.lazy`.