Simplify enable DND / choose DND QS duration dialogs to use proper RadioButtons

Instead of a complex layout (one RadioButton plus two TextViews per option) so that the options could have two lines of text. The same can be achieved with a Spanned text in the RadioButton, which removes the unnecessary double a11y focus targets (and simplifies the code significantly).

It also looks nicer (better aligned and and no longer truncates the text) at very high font sizes.

Fixes: 422065897
Fixes: 380493533
Test: atest DndDurationDialogFactoryTest EnableDndDialogFactoryTest + manual with Talkback + manual with max and min font size
Flag: EXEMPT Simple bugfix
Change-Id: Id691921484544ae28a97004f1434793bb2745be3