Avoid waiting for user actions when kwin Focus stealing prevention is high or extreme

Summary:
When kwin focus stealing prevention is high or extreme, I had to activate manually the tests windows for the test to continue.
Now it is activated without human intervention.

Test Plan: kfilewidgettest and kfileplaceswidgettest pass without human intervention.

Reviewers: dfaure, Frameworks

Reviewed By: dfaure

Subscribers: kde-frameworks-devel

Tags: Frameworks

Differential Revision: https://phabricator.kde.org/D16072