public ActionResult SetValidityDates(SetValidityDatesCommand command)
        {
            if (!ModelState.IsValid)
            {
                return(View());
            }

            _changeDatesHandler.Handle(command);

            return(RedirectToAction("Details", new { id = command.PromotionId }));
        }
        public ActionResult SetValidityDates(SetValidityDatesCommand command)
        {
            if (!ModelState.IsValid)
            {
                return View();
            }

            _changeDatesHandler.Handle(command);

            return RedirectToAction("Details", new { id = command.PromotionId });
        }