[scripting] Expose Workspace::sendClientToDesktop()
Summary:
BUG: 416093
FIXED-IN: 5.18.0
Test Plan: Only compile-time check.
Reviewers: KWin, davidedmundson
Reviewed By: KWin, davidedmundson
Subscribers: kwin
Tags: KWin
Differential Revision: https://phabricator.kde.org/D26988