Set JSX as default mode for the editor

Author: rvsia

packages/react-renderer-demo/src/app/src/components/code-editor/index.js

@@ -27,6 +27,7 @@ const CodeEditor = (props) => (
     onLoad={(editor) => {
       editor.getSession().setUseWorker(false);
     }}
+    mode="jsx"
     {...props}
   />
 );