Versionned HTML documentations are served as text/plain

[pchampin]

E.g.: https://purl.org/pav/2.3/html → https://cdn.jsdelivr.net/gh/pav-ontology/pav@2.3.1/pav.html
and similarly for other versions.

Is it possible to ask JsDeliver to serve text/html instead?
If not, is it possible to consider an alternative backend for the purl.org URLs?

(there are not so many versions, so having all version snapshots hosted on github pages, alongside the "evergreen" version, seems like a doable workaround)