Summary:
All other KCMs have their {nav Get New [things]...} buttons in the bottom-right corner. This patch adjusts KWin's KCMs to adopt the same convention there too.
With this patch, all KCMs will have their GHNS buttons in the same location.
Closes T9954
Test Plan:
{F6375278}
{F6375277}
{F6375276}
{F6375275}
Reviewers: #kwin, #vdg, zzag
Reviewed By: #kwin, zzag
Subscribers: Codezela, kwin, kde-doc-english
Tags: #kwin, #documentation
Maniphest Tasks: T9954
Differential Revision: https://phabricator.kde.org/D16537
