修复直接支付导致的问题

manage-server/app/Http/Controllers/ProductOrderController.php

                         "product_photo" => $product->photo
                     ]);
                 $shopcar = Shopcar::where("wechat_id", $wechat_id)->where("product_id", $id)->first();
-                $shopcar->delete();
-
+                if ($shopcar) {
+                    $shopcar->delete();
+                }
             }
             $productOrder->price = $total;
             $productOrder->save();