Stock proxy typo fix

src/platform/abstract/stock.js

@@ -42,7 +42,7 @@ class AbstractStockProxy {
    *
    */
   check (sku) {
-    throw new Error('UserProxy::check must be implemented for specific platform')
+    throw new Error('StockProxy::check must be implemented for specific platform')
   }
 }
 

src/platform/magento2/stock.js

@@ -1,7 +1,7 @@
-import AbstractUserProxy from '../abstract/user'
+import AbstractStockProxy from '../abstract/stock'
 import { multiStoreConfig } from './util'
 
-class StockProxy extends AbstractUserProxy {
+class StockProxy extends AbstractStockProxy {
   constructor (config, req) {
     const Magento2Client = require('magento2-rest-client').Magento2Client;
     super(config, req)