Use the new JSX transform (#25064)

app/javascript/mastodon/features/ui/components/link_footer.jsx

@@ -1,5 +1,5 @@
 import { connect } from 'react-redux';
-import React from 'react';
+import { PureComponent } from 'react';
 import PropTypes from 'prop-types';
 import { FormattedMessage, defineMessages, injectIntl } from 'react-intl';
 import { Link } from 'react-router-dom';
@@ -24,7 +24,7 @@ const mapDispatchToProps = (dispatch, { intl }) => ({
   },
 });
 
-class LinkFooter extends React.PureComponent {
+class LinkFooter extends PureComponent {
 
   static contextTypes = {
     identity: PropTypes.object,