private DateTime?CheckRentedMovie(StatusMovie statusMovie, int days)
 {
     if (statusMovie == StatusMovie.Rented)
     {
         return(DateTime.Now.AddDays(days));
     }
     return(null);
 }
        private async Task UpdateStock(int stockId, CancellationToken cancellationToken, StatusMovie statusMovie)
        {
            var stock = await _context.Stocks.FindAsync(stockId);

            stock.IsAvailable = false;

            await _context.SaveChangesAsync(cancellationToken);
        }