Seems like period/dot in filename breaks the GH action

[praiskup]

The leap-15.4.config has not been detected: rpm-software-management/mock#1464

[webknjaz]

Technically, that's expected due to the semantics of how Towncrier itself perceives the fragments. You probably need to fix your usage of Towncrier. Either replace the period with an underscore or a dash, or perhaps even go for an orphan fragment (starting with a leading + which is special-cased in Towncrier).
Usually, the first part is the issue/PR number to be linked. Why didn't you want to follow that format?

[praiskup]

I opened this, because we hit a real-life issue with towncrier:

$ towncrier create foo.bar.baz.config
Created news fragment at /home/praiskup/rh/projects/mock/mock/releng/release-notes-next/foo.bar.baz.config

At least we were allowed to create such file, I assumed that it "is a correct snippet" then, and I'd expect that the action accepts it as well. But is this a bug of towncrier create?