fix abs移除

Src/Dlhis.Canteen/Order/Request/BalanceHainingImportRequest.cs

@@ -26,7 +26,6 @@ public class BalanceHainingImportRequest : IValidatableObject
     /// <summary>
     /// 金额
     /// </summary>
-    [Required]
     public decimal Amount { get; set; }
 
     /// <summary>
@@ -109,8 +108,6 @@ public class BalanceHainingImportRequest : IValidatableObject
         }
         else
         {
-            Amount = Math.Abs(Amount);
-
             if (ApplicationType != CanteenApplicationTypeEnumType.MealSupplement)
             {
                 yield return new ValidationResult("只支持餐补充值", new[] { nameof(ApplicationType) });