public int CreateReminder(int categoryId, CreateToDoReminderDto newReminder)
        {
            var category   = GetCategoryById(categoryId);
            var reminderDb = _mapper.Map <ToDoReminder>(newReminder);

            reminderDb.CategoryId = category.Id;

            _appDbContext.ToDoReminders.Add(reminderDb);
            _appDbContext.SaveChanges();

            return(reminderDb.Id);
        }
        public ActionResult Create([FromRoute] int categoryId, [FromBody] CreateToDoReminderDto newReminder)
        {
            var newId = _reminderService.CreateReminder(categoryId, newReminder);

            return(Created($"/category/{categoryId}/reminder/{newId}", null));
        }