Update BaseTransferInformation.php

Necessary else clause, because otherwise it will not multiply non-floats with 100,which leads as a result to wrong transferAmount values. The $amount of 100 would be saved as transferAmount = 100, which generates a wrong value of 10.00 EUR when converted back to SEPA-Amount in CustomDirectDebitTransferDomBuilder->inToCurrency in visitTransferInformation().