Ensure that sessions are pinged by default.

If sessions are being returned and borrowed quickly, the difference in ticks may be zero (because the system timer isn't high-resolution); the default value of ConnectionIdlePingTime=0 will now ping all sessions and users have to explicitly set it to a non-zero value to opt out.

Author: bgrainger

src/MySqlConnector/Core/ConnectionPool.cs

@@ -71,7 +71,7 @@ public async ValueTask<ServerSession> GetSessionAsync(MySqlConnection connection
 						{
 							reuseSession = await session.TryResetConnectionAsync(ConnectionSettings, ioBehavior, cancellationToken).ConfigureAwait(false);
 						}
-						else if ((unchecked((uint) Environment.TickCount) - session.LastReturnedTicks) > ConnectionSettings.ConnectionIdlePingTime)
+						else if ((unchecked((uint) Environment.TickCount) - session.LastReturnedTicks) >= ConnectionSettings.ConnectionIdlePingTime)
 						{
 							reuseSession = await session.TryPingAsync(ioBehavior, cancellationToken).ConfigureAwait(false);
 						}