团购活动：定时退费

shared/db/ActivityGroupShopUserRec.ts

@@ -30,9 +30,6 @@ export class GroupShopBuyRecord {
   @prop({ required: true })
   buyCnt: number;			           // 购买次数
 
-  @prop({ required: true })
-  refundPrice: number;	        // 退费价格
-
   constructor(curDiscount: GroupShopDiscount, buyCnt: number) {
     this.time = nowSeconds();
     if(curDiscount) {
@@ -42,7 +39,6 @@ export class GroupShopBuyRecord {
       this.price = curDiscount.price;
     }
     this.buyCnt = buyCnt;
-    this.refundPrice = 0;
   }
 }