[requirements] [ironic] Bumping test-requirements on stable/train for the PDF goal?

Hi all,

we (ironic) have a few deliverables that got the PDF goal fulfilled after stable/train was branched. Is it reasonable to still pursue the goal on stable/train even if it requires raising the openstackdoctheme requirement?

An example is https://review.opendev.org/#/c/682274/

Thanks, Dmitry