Format quickstart output (#1800)

Just a little docs thing...
The JSON output in the quickstart example isn't formatted as
stated/expected.

website/docs/quickstart.md

@@ -162,7 +162,7 @@ function Component() {
   })
 
   return (
-    <pre>{ JSON.stringify(data) }</pre>
+    <pre>{ JSON.stringify(data, null, 2) }</pre>
   )
 }