Last pdf filters/markers fixes and translation backports

1. Fixes multiple bugs with pdf export !4538 (merged)
   • multipage, filter on group on second page #3214 (closed) (should already be documented as fixed, this is a follow-up)
   • multipage, clone of filtered item #3635 (closed) (follow-up of above, well, only noticable after filters start showing up!)
   • if marker is defined outside of def, pdf export doesn't render a copy of it (#3566 (closed))
   • marker colors lost with marker created within Inkscape (not every marker) #3498 (closed)
2. Copy paste of some japanese translations. Done since that translation was at 100%, and was kept up to date on master, might as well keep it updated here too. Follow-up to 2d9f7a73
3. Updated Hungarian man page translation (Taken from !4588 (closed) but updated for the true/false string, see !4587 (closed) . I'll take this out if the mr is merged but I don't want to forget!)
4. Vietnamese translations taken from !4489 (merged)
5. Remove unnecessary warning (!4581 (merged), no issue)

Update: force pushed to fix compilation (forgot to make a couple changes when making the functions const, taken from 9ea9302e)
Update(2): fix some of the codequality warnings