public async Task Fail_CostHasBeenApproved_Empty_CostId()
        {
            //Arrange
            var costId         = Guid.Empty;
            var approverUserId = _approverUserId;
            var approvalType   = ApprovalType.Brand.ToString();

            //Act
            bool result = await _emailNotificationService.CostHasBeenApproved(costId, approverUserId, approvalType);

            //Assert
            result.Should().BeFalse();
            _paperPusherClientMock.Verify(p => p.SendMessage(It.IsAny <EmailNotificationMessage <CostNotificationObject> >()), Times.Never);
        }