KDesktopFileActions: port from KRun::run to KIO::ApplicationLauncherJob

Summary:
Remove KService::Ptr parameter from ApplicationLauncherJob, the
KServiceAction is now sufficient.

Test Plan: dolphin, RMB, "Checkout from a repository..." (requires kdesvn) still works

Reviewers: davidedmundson, apol, broulik

Reviewed By: apol, broulik

Subscribers: kde-frameworks-devel

Tags: Frameworks

Differential Revision: https://phabricator.kde.org/D28268