fix: 已退数量

src/views/sales_control/sales_management/components/return_sales_form.vue

@@ -114,10 +114,10 @@ export default {
         },
 
         {
-          prop: '',
+          prop: 'diffQty',
           label: '已退数量',
           width: '180',
-          isCustom: true
+          // isCustom: true
         },
         // {
         //   prop: 'totalVolume',