Hyperlink commit hashes in the outout of git describe

[hexagonrecursion]

Currently github hyperlinks commit hashes like this: 85d8952 which is super useful. git-describe produces outputs like this:

0.29.0.gfm.0-27-g85d8952

Format: "$tag-$commits_since_tag-g$commit"

It would be great if 85d8952 was hyperlinked in this case too.