Retiring python-descartes

Hi, I am retiring python-descartes in Rawhide. Upstream died when Bitbucket dropped Mercurial support, and has no intention of reviving it. Downstream users have stopped using it, and I have removed the unnecessary dependency from Fedora packages, or patched it out after reporting upstream. It is currently FTBFS with Python 3.10, and thus not installable after the rebuild. -- Elliott