Remove React, PureComponent global import, added those imports to files directly

• Remove:
- React, PureComponent global import and added those imports to files directly

app/javascript/gabsocial/components/shop_item.js

@@ -1,8 +1,9 @@
+import React from 'react'
 import { DEFAULT_REL } from '../constants'
 import Image from './image'
 import Text from './text'
 
-class ShopItem extends PureComponent {
+class ShopItem extends React.PureComponent {
 
   render() {
     const {