Update src/Picqer/Financials/Exact/DocumentType.php
Update src/Picqer/Financials/Exact/DocumentType.php

Co-Authored-By: freddyamsterdam <c22b5f9178342609428d6f51b2c5af4c0bde6a42@freddydenoord.nl>
picqer/exact-php-client,picqer/exact-php-client