Fix the layout direction of 3 widgets

Summary:
Fix the layout direction of some settings widgets.
Forcing LeftToRight made the page left to right in right to left layouts.
Forcing RightToLeft made the checkbox's box to the right of the text instead of being to the left (in LTR
layouts).

Test Plan: Logic.

Reviewers: Krita, rempt

Reviewed By: Krita, rempt

Subscribers: rempt, ngraham

Tags: Krita

Differential Revision: https://phabricator.kde.org/D15329