Use the new JSX transform (#25064)

app/javascript/mastodon/components/load_gap.jsx

@@ -1,4 +1,4 @@
-import React from 'react';
+import { PureComponent } from 'react';
 import PropTypes from 'prop-types';
 import { injectIntl, defineMessages } from 'react-intl';
 import { Icon }  from 'mastodon/components/icon';
@@ -7,7 +7,7 @@ const messages = defineMessages({
   load_more: { id: 'status.load_more', defaultMessage: 'Load more' },
 });
 
-class LoadGap extends React.PureComponent {
+class LoadGap extends PureComponent {
 
   static propTypes = {
     disabled: PropTypes.bool,