Fixes <http://issues.guix.gnu.org/issue/30345> and
finally fixes <http://issues.guix.gnu.org/issue/25020>.
Formerly packages living in a path like
/stable/frameworks/5.60/portingAids/kross-5.60.0.tar.xz
have not been found.
* guix/import/kde.scm (uri->kde-path-pattern): New procedure.
(latest-kde-release): Use pattern to search for file.