fix build

Author: oliviertassinari

docs/pages/blog/2021-q2-update.js

@@ -1,6 +1,6 @@
 import * as React from 'react';
 import TopLayoutBlog from 'docs/src/modules/components/TopLayoutBlog';
-import { docs } from '!@material-ui/markdown/loader!./2021-q2-update.md';
+import { docs } from './2021-q2-update.md?@material-ui/markdown';
 
 export default function Page() {
   return <TopLayoutBlog docs={docs} />;