Summary:
This wasn't used on startup (ksmserver calls KProcess)
Nor for the rules dialog (kwin invokes it with QProcess)
We may as well simplify the code and drop the dependency
See also T12140
Test Plan:
Restarted
Opened the rules dialog
Reviewers: #kwin, zzag
Reviewed By: #kwin, zzag
Subscribers: kwin
Tags: #kwin
Differential Revision: https://phabricator.kde.org/D26835