/// <summary>
        /// Delete an existing watchlist.
        /// </summary>
        /// <param name="userId">The unique identifier of the user who owns the watchlist.</param>
        /// <param name="watchlistId">The unique identifier of the watchlist to delete.</param>
        public void DeleteWatchlist(Guid userId, Guid watchlistId)
        {
            Validate.NotEmpty(userId, nameof(userId));
            Validate.NotEmpty(watchlistId, nameof(watchlistId));

            Watchlist watchlist = GetWatchlist(userId, watchlistId);

            _watchlistRepository.Delete(watchlist);
        }
 public void Delete(Watchlist watchlist)
 {
     _watchlistRepository.Delete(watchlist);
 }