Use default behavior for ExecuteScalar.

Specifying those flags had no effect previously; removing them reverts ExecuteScalar to its behavior in 0.56.0 instead of silently opting it into the new behaviour (which might have unknown side effects).

Author: bgrainger

src/MySqlConnector/MySql.Data.MySqlClient/MySqlCommand.cs

@@ -244,7 +244,7 @@ internal async Task<object> ExecuteScalarAsync(IOBehavior ioBehavior, Cancellati
 			this.ResetCommandTimeout();
 			var hasSetResult = false;
 			object result = null;
-			using (var reader = (MySqlDataReader) await ExecuteReaderAsync(CommandBehavior.SingleResult | CommandBehavior.SingleRow, ioBehavior, cancellationToken).ConfigureAwait(false))
+			using (var reader = (MySqlDataReader) await ExecuteReaderAsync(CommandBehavior.Default, ioBehavior, cancellationToken).ConfigureAwait(false))
 			{
 				do
 				{