I saw it in this repo.
My doubt is, how is that the tags of releases points to branch with just one commit? How do you do that?
Why would you want to do such a thing? It doesn't make too much sense, what is the use-case?
Anyway, just make a new orhpan branch with
git checkout --orphan, then create a commit, tag it and eventually delete the branch again. Et voilá, you have a tag that points to a commit without history and not on any branch.