[IBR-097-OM] - If category is 'Z' in accounting currency, rate MUST be 0.
IBR-097-OMubl:Invoice/cac:TaxTotal/cac:TaxSubtotal | cn:CreditNote/cac:TaxTotal/cac:TaxSubtotalnot($taxCurrency != '' and $isTaxCurrency and $cat='O') or (cac:TaxCategory/cbc:Percent castable as xs:decimal and xs:decimal(cac:TaxCategory/cbc:Percent) = 0)