Fix hydrate root link (#4937)

* add loading indicator to sidebar links

* fix link typo

beta/src/pages/apis/react-dom/hydrate.md

@@ -3,7 +3,7 @@ title: hydrate
 ---
 <Gotcha>
 
-In React 18, `hydrate` was replaced by [`hydrateRoot`](/apis/react-dom/client/createRoot). Using `hydrate` in React 18 will warn that your app will behave as if it’s running React 17. Learn more [here](https://reactjs.org/blog/2022/03/08/react-18-upgrade-guide.html#updates-to-client-rendering-apis).
+In React 18, `hydrate` was replaced by [`hydrateRoot`](/apis/react-dom/client/hydrateRoot). Using `hydrate` in React 18 will warn that your app will behave as if it’s running React 17. Learn more [here](https://reactjs.org/blog/2022/03/08/react-18-upgrade-guide.html#updates-to-client-rendering-apis).
 
 </Gotcha>