【多店2.3.0】收银台加入购物车在此重新选择规格问题

1、文件：app/services/order/StoreCartServices.php
2、方法：modifyCashierCart

public function modifyCashierCart(int $storeId, int $cart_id, int $product_id, string $unique)
    {
        /** @var StoreProductAttrValueServices $attrService */
        $attrService = app()->make(StoreProductAttrValueServices::class);
        $stock = $attrService->value(['product_id' => $product_id, 'unique' => $unique, 'type' => 0], 'stock');
        if ($stock > 0) {
            $this->dao->update($cart_id, ['product_attr_unique' => $unique, 'cart_num' => 1]);
        } else {
            throw new ValidateException('选择的规格库存不足');
        }
    }

3、直接替换掉该方法，然后重启swoole