Download abevjava_install.jar from source
Some documents require the newest version of ÁNYK. It could be downloaded from: https://nav.gov.hu/pfile/programFile?path=/nyomtatvanyok/letoltesek/nyomtatvanykitolto_programok/nyomtatvany_apeh/keretprogramok/AbevJava instead of manual updating in GitHub repo
The appeal of Docker images is reproducibility, which is lost when the build relies on an external download. Since ÁNYK appears to be a quite dodgy piece of patchwork, I'd prefer new bugs to appear in new versions of the image instead. 😄
I think a new switch could be implemented in build-image.sh, which can download the newest jar. So, the saved jar in repo can be updated manually, but if someone wants to use the newest ÁNYK (because some documents needs it), he/she could use this switch and it would be easier.