public IActionResult Add(PositionsViewModel dto)
        {
            if (!ModelState.IsValid)
            {
                dto.Positions = positionManager.GetDistinctNames();
                dbManager.Commit();
                return(View("Add", dto));
            }
            positionManager.CreateNewPosition(dto, out string message);
            dbManager.Commit();

            var res = new ResultViewModel(message, message, $"/positions", "Назад");

            return(View("Result", res));
        }