fix(sixshop-wechatpay): 修改支付时的描述信息

src/PaymentProvider.php

@@ -86,7 +86,7 @@ class PaymentProvider implements PaymentProviderInterface
                 openid: $openid,
                 outTradeNo: $payment['out_trade_no'],
                 total: (int)($payment['amount'] * 100),
-                description: '订单：' . $order['order_sn'],
+                description: ($order['description'] ?? '') ?: '订单：' . $order['order_sn'],
                 expireTime: $expireTime
             );
             $payment->payment_param = $this->paymentParams($payment->payment_param->prepay_id);