fix(lakala): 强制商品ID为字符串类型

- 将商品ID转换为字符串以确保数据类型一致性
- 避免因整数类型导致的潜在支付参数错误
- 保证与拉卡拉支付接口的商品ID字段类型匹配

src/PaymentProvider.php

@@ -95,7 +95,7 @@ class PaymentProvider implements PaymentProviderInterface
         $goodsDetailList = [];
         foreach ($order['order_goods'] as $goods) {
             $goodsDetail = new TradePreorderWechaGoodsDetail();
-            $goodsDetail->setGoodsId($goods['goods_id']);
+            $goodsDetail->setGoodsId((string)$goods['goods_id']);
             $goodsDetail->setQuantity($goods['num']);
             $goodsDetail->setPrice(round($goods['price'] * 100, 0));
             $goodsDetail->setGoodsName($goods['goods_name']);