feat(react): Update docs to React 18 instructions (#6568)

Author: AbhiPrasad

src/platform-includes/getting-started-config/javascript.react.mdx

@@ -1,6 +1,6 @@
 ```javascript
+import { createRoot } from "react-dom/client";
 import React from "react";
-import ReactDOM from "react-dom";
 import * as Sentry from "@sentry/react";
 import App from "./App";
 
@@ -13,10 +13,9 @@ Sentry.init({
   tracesSampleRate: 1.0,
 });
 
-ReactDOM.render(<App />, document.getElementById("root"));
-
-// Can also use with React Concurrent Mode
-// ReactDOM.createRoot(document.getElementById('root')).render(<App />);
+const container = document.getElementById(“app”);
+const root = createRoot(container);
+root.render(<App />);
 ```
 
 Once this is done, all unhandled exceptions are automatically captured by Sentry.

src/wizard/javascript/react/index.md

@@ -26,7 +26,7 @@ npm install --save @sentry/react
 Initialize Sentry as early as possible in your application's lifecycle.
 
 ```javascript
-import { createRoot } React from "react-dom/client";
+import { createRoot } from "react-dom/client";
 import React from "react";
 import * as Sentry from "@sentry/react";
 import App from "./App";
@@ -39,7 +39,7 @@ Sentry.init({
 
 const container = document.getElementById(“app”);
 const root = createRoot(container);
-root.render(<App />)
+root.render(<App />);
 ```
 
 > **tracesSampleRate: 1.0**
@@ -59,4 +59,4 @@ return <button onClick={() => methodDoesNotExist()}>Break the world</button>;
 
 - [Source Maps](https://docs.sentry.io/platforms/javascript/guides/react/sourcemaps/): Learn how to enable readable stack traces in your Sentry errors.
 - [React Features](https://docs.sentry.io/platforms/javascript/guides/react/features/): Learn about our first class integration with the React framework.
-- [Session Replay](https://docs.sentry.io/platforms/javascript/guides/react/session-replay/): Get to the root cause of an error or latency issue faster by seeing all the technical details related to that issue in one visual replay on your web application.
+- [Session Replay](https://docs.sentry.io/platforms/javascript/guides/react/session-replay/): Get to the root cause of an error or latency issue faster by seeing all the technical details related to that issue in one visual replay on your web application.