public async Task <Bid> AddAsync(Bid bid)
        {
            await _bidDbContext.Bids.AddAsync(bid);

            await _bidDbContext.SaveChangesAsync();

            return(bid);
        }
        public async Task <AuctionItem> UpdateItemAsync(AuctionItem item)
        {
            var dbItem = await _bidDbContext.AuctionItems.SingleOrDefaultAsync(i => i.ItemId == item.ItemId);

            dbItem.BuyerUserId = item.BuyerUserId;
            _bidDbContext.Entry(dbItem).State = EntityState.Modified;
            await _bidDbContext.SaveChangesAsync();

            return(dbItem);
        }