优化google feed

app/code/Joshine/GoogleFeed/Console/Command/GoogleFeed.php

@@ -342,7 +342,7 @@ class GoogleFeed extends Command
             $data['size'] = $sizeText;
             $data['item group id'] = $mpu;
             $data['material'] = '';
-            $data['shipping(country:price)'] =':'. $this->scopeConfigInterface->getValue('carriers/flatrate/price') . ' USD';
+            $data['shipping(country:price)'] ='US:'. $this->scopeConfigInterface->getValue('carriers/flatrate/price') . ' USD';
             $data['shipping weight'] = $product->getWeight();
             $data['custom label 0'] = '';
             $data['custom label 1'] = '';