解决小程序二维码生成有误的 bug

@@ -157,7 +157,7 @@ class GroupPurchaseContainer extends Component {
         } = this.props.app;
 
         let param = {
-            activity_id: activityId,
+            activityId,
         }
 
         let qrCode = host + '/wechat/miniapp/img-check.jpg?param=' + encodeURIComponent(JSON.stringify(param)) + '&miniQrType=15';