public ActionResult MarkAsComplete(MarkPromotionAsReadyCommand command)
        {
            if (!ModelState.IsValid)
            {
                return View();
            }

            _markAsReadyHandler.Handle(command);
            return RedirectToAction("Index");
        }
        public ActionResult MarkAsComplete(MarkPromotionAsReadyCommand command)
        {
            if (!ModelState.IsValid)
            {
                return(View());
            }

            _markAsReadyHandler.Handle(command);
            return(RedirectToAction("Index"));
        }