message: fix(render-react): prevent invalid css injections
diff: @@ -6,5 +6,10 @@ module.exports = render;
  function render(Component) {
  const component = React.createElement(Component.default || Component);
  const html = ReactDOMServer.renderToString(component);
  - return { html, css: `<style>${Component.css}</style>` };
  +
  + const css = typeof Component.css === 'string' && Component.css !== ''
  + ? `<style>${Component.css}</style>`
  + : undefined;
  +
  + return { html, css };
  }
  