LPS-42399 MailEngine send exception handling

Hi Julio.

This pr is done in order to fix LPS-42399.  

The origin of this ticket was discussed in https://in.liferay.com/web/global.engineering/forums/-/message_boards/message/1886462?p_p_auth=W6rUSt7H

With this fix, if you don't change the added preference, the behavior is the same as before. When the property is set to true,  if the send mail method fails, an  exception will be thrown.

I sent this pr to Neil Griffin before, but he didn't answer me.