fix(text preference): fix preview block ui broken in SUW

As previous cl ag/25185014 we increased the preview block horizontal padding when landscape mode. However, in setup wizard it uses GlifPreferenceLayout so the settings page only has half screen width when landscape mode, so the preview block ui is squished due to limited width. Also, setup wizard package has overlay the paddings to larger than our prevoius adjust. Therefore, we rollback the changes in accessibility_text_reading_preview.xml to get the default padding, then add checker to increase the paddings if needed at runtime.

Bug: 309590083
Test: manually
Test: atest TextReadingPreviewPreferenceTest
Test: atest TextReadingPreferenceFragmentForSetupWizardTest
Change-Id: Ib907f4182eed272b84a4ab6208ea2d8a89ba96c4