Update bubble expanded view size and margins

This change updates the bubble expanded view on large screens according to specs
https://www.figma.com/file/00VWOwhcuElG8StuLKYu5Z/Bubbles?type=design&node-id=4693-139011&mode=design&t=U6QGHMrGe0K1zY93-0

Also see:
https://screenshot.googleplex.com/AaxBXDdr7s4RmWS
https://screenshot.googleplex.com/6xavE6hnxVqT36E

Fixes: 301232987
Test: atest BubblePositionerTest

Change-Id: Ib01c240594a761b553cc853a8a077cb54cee7679