Bug 1744: Failure when .NET assembly times out waiting for WinSCP to start

https://winscp.net/tracker/1744

Source commit: e74da8e68f05aff936783ccc7af7e35de6948e6a

dotnet/Session.cs

@@ -1897,7 +1897,10 @@ namespace WinSCP
                 {
                     message += " - " + additional;
                 }
-                _logReader.SetTimeouted();
+                if (_logReader != null)
+                {
+                    _logReader.SetTimeouted();
+                }
                 throw Logger.WriteException(new TimeoutException(message));
             }