SpecifiedTradePaymentTerms should be [0..n], but is [0..1]

[sude22]

Hello,
and first of all thank you for the great work on this project.

When importing an invoice, I noticed that there is a property "PaymentTerms". It is filled with the content from "SpecifiedTradePaymentTerms".
However, in my invoice there are two"SpecifiedTradePaymentTerms" sections.

Shouldn't the "PaymentTerms" property then be a list?

Example:
<ram:SpecifiedTradePaymentTerms>
<ram:Description>Zahlbar bis 07.01.2024 ohne Abzug</ram:Description>
<ram:DueDateDateTime>
<udt:DateTimeString format="102">20240107</udt:DateTimeString>
</ram:DueDateDateTime>
</ram:SpecifiedTradePaymentTerms>
<ram:SpecifiedTradePaymentTerms>
<ram:Description>Zahlbar bis 15.12.2023 3,00% Skt= 1039,84</ram:Description>
<ram:DueDateDateTime>
<udt:DateTimeString format="102">20231215</udt:DateTimeString>
</ram:DueDateDateTime>
<ram:ApplicableTradePaymentDiscountTerms>
<ram:BasisAmount currencyID="EUR">1072.00</ram:BasisAmount>
<ram:CalculationPercent>3.00</ram:CalculationPercent>
</ram:ApplicableTradePaymentDiscountTerms>
</ram:SpecifiedTradePaymentTerms>

BTW: It would be excellent if the fields in "ApplicableTradePaymentDiscountTerms" could also be imported, as then automatic processing of the discount values would be possible.

[stephanstapel]

Thanks for your initiative!
I'd be more than happy if you could issue a pull request. Please remember to implement both reader and write and add test cases