Use ReactDOM.createRoot over old style

Signed-off-by: Matthew Peveler <[email protected]>

example/src/index.js

@@ -1,7 +1,8 @@
 import React from 'react';
-import ReactDOM from 'react-dom';
+import { createRoot } from 'react-dom/client';
 
 import './index.css';
 import App from './App';
 
-ReactDOM.render(<App />, document.getElementById('root'));
+const root = createRoot(document.getElementById('root'));
+root.render(<App />);