https://bugzilla.redhat.com/show_bug.cgi?id=2136778
--- Comment #8 from Sandro gui1ty@penguinpee.nl --- Thanks for the clarification. I was going by the Licensing Guide, which says:
"If the source package includes the text of the license(s) in its own file, then that file, containing the text of the license(s) for the package must be included in %license"
That made me think the LICENSE file has to be explicitly included as %license LICENSE. If the marking by %pyproject_save_files is sufficient, I guess I can clean up my own spec files and remove the explicit %license LICENSE, which indeed duplicates the LICENSE file.