Fix hydration on site

This fixes an incorrect patch applied in 427bcad, which should not
have changed.

Related-to: 427bcad.
Closes GH-2020.

docs/_asset/index.client.js

@@ -1,5 +1,5 @@
 import React from 'react'
-import {createRoot} from 'react-dom/client'
+import {hydrateRoot} from 'react-dom/client'
 import {createFromFetch} from 'react-server-dom-webpack'
 import {Root} from './root.client.js'
 
@@ -14,6 +14,5 @@ if ('paintWorklet' in CSS) {
 async function main() {
   const nljson = document.querySelector('#payload').dataset.src
   const $root = document.querySelector('#root')
-  const root = createRoot($root)
-  root.render(<Root response={createFromFetch(fetch(nljson))} />)
+  hydrateRoot($root, <Root response={createFromFetch(fetch(nljson))} />)
 }