Map keywords to dc:subject in OAI

[wendycr]

In order to share the best metadata possible with other systems, it would be helpful if keywords could be mapped to the dc:subject in the OAI. Best practice is a controlled vocabulary, but keywords would be better than nothing - https://www.dublincore.org/specifications/dublin-core/dcmi-terms/#http://purl.org/dc/elements/1.1/subject

[alainna]

is this something that's done in https://github.com/BirkbeckCTP/janeway/pull/3098 ?