Collapse the sections in the room list on Home page

[AmandineLP]

as i can't ignore invites yet, i have a bunch piling up that i don't want to either accept or decline and it takes all my screen.

Designs are here: https://www.figma.com/file/QugKzfgL4gISlsmluw9EVb/Change-expandable-headers?node-id=1%3A5509

For iOS we need to:

• Add the collapse and expand header to all sections
• move the notification count to be right-aligned

from	to

[daniellekirkwood]

This issue is also on Android

[daniellekirkwood]

@amshakal When you have a second could you link the figma &/ add screenshots that shows the desired Android behaviour. I believe all we need to do for this issue is to add the Expand/Collapse arrows (as the number is already visible)

[amshakal]

Link to designs: https://www.figma.com/file/QugKzfgL4gISlsmluw9EVb/Change-expandable-headers?node-id=1%3A5509