【代码优化】商城：优惠劵的描述字段新增

Author: YunaiV

src/views/mall/promotion/coupon/template/CouponTemplateForm.vue

@@ -336,6 +336,7 @@ const resetForm = () => {
   formData.value = {
     id: undefined,
     name: undefined,
+    description: undefined,
     discountType: PromotionDiscountTypeEnum.PRICE.type,
     discountPrice: undefined,
     discountPercent: undefined,