Change variable name to avoid PUA character. Fixes #1502

This should improve compatibility with servers that don't accept Unicode characters in identifiers.

src/MySqlConnector/Core/ServerSession.cs

@@ -2131,8 +2131,8 @@ protected override void OnStatementBegin(int index)
 	private static readonly PayloadData s_setNamesUtf8mb4NoAttributesPayload = QueryPayload.Create(false, "SET NAMES utf8mb4;"u8);
 	private static readonly PayloadData s_setNamesUtf8WithAttributesPayload = QueryPayload.Create(true, "SET NAMES utf8;"u8);
 	private static readonly PayloadData s_setNamesUtf8mb4WithAttributesPayload = QueryPayload.Create(true, "SET NAMES utf8mb4;"u8);
-	private static readonly PayloadData s_sleepNoAttributesPayload = QueryPayload.Create(false, "SELECT SLEEP(0) INTO @\uE001MySqlConnector\uE001Sleep;"u8);
-	private static readonly PayloadData s_sleepWithAttributesPayload = QueryPayload.Create(true, "SELECT SLEEP(0) INTO @\uE001MySqlConnector\uE001Sleep;"u8);
+	private static readonly PayloadData s_sleepNoAttributesPayload = QueryPayload.Create(false, "SELECT SLEEP(0) INTO @__MySqlConnector__Sleep;"u8);
+	private static readonly PayloadData s_sleepWithAttributesPayload = QueryPayload.Create(true, "SELECT SLEEP(0) INTO @__MySqlConnector__Sleep;"u8);
 	private static readonly PayloadData s_selectConnectionIdVersionNoAttributesPayload = QueryPayload.Create(false, "SELECT CONNECTION_ID(), VERSION();"u8);
 	private static readonly PayloadData s_selectConnectionIdVersionWithAttributesPayload = QueryPayload.Create(true, "SELECT CONNECTION_ID(), VERSION();"u8);
 

tests/MySqlConnector.Tests/FakeMySqlServerConnection.cs

@@ -158,7 +158,7 @@ public async Task RunAsync(TcpClient client, CancellationToken token)
 								m_server.CancelQuery(connectionId);
 								await SendAsync(stream, 1, WriteOk);
 							}
-							else if (query == "SELECT SLEEP(0) INTO @\uE001MySqlConnector\uE001Sleep;")
+							else if (query == "SELECT SLEEP(0) INTO @__MySqlConnector__Sleep;")
 							{
 								var wasSet = CancelQueryEvent.Wait(0, token);
 								await SendAsync(stream, 1, WriteOk);