public virtual void Detects_invalid_concurrency_token()
        {
            var modelBuilder = CreateConventionalModelBuilder();

            modelBuilder.Entity <Customer>()
            .ToContainer("Orders")
            .Property <string>("_not_etag")
            .IsConcurrencyToken();

            var model = modelBuilder.Model;

            VerifyError(CosmosStrings.NonEtagConcurrencyToken(typeof(Customer).Name, "_not_etag"), model);
        }