Update suggestion card width.

- instead of using hard-coded width for 1 or 2 cards, they should take
up the whole screen width minus the defined padding, so that when the
device is in landscape mode, they look better.

Change-Id: Ic6485c858c7742a154a6d9b05fff180f161be323
Fixes: 72850225
Test: make RunSettingsRoboTests