Exception getException() {
		return exc;
	}
Returns an IOException, LoginException or RuntimeException
if handle is null after running task.  If both the exception
and handle are null, it implies the connection attempt was cancelled
by the user.
@return exception which occured during a failed connection attempt, or null
Ghidra/Framework/FileSystem/src/main/java/ghidra/framework/client/ServerConnectTask.java