Limit the suggestions to be shown to 5.

- when creating the dashboard data, pass the sublist of suggestions to
cap the total number of suggestions to be shown to 5.
- if user swipe away the suggestion, it will only remove the suggestion
from the suggestion adapater, and will not trigger rebuilding the whole
UI.

Bug: 64072051
Change-Id: I1efabeb2a805c670007c631d3ccb0fdfbde7b55a
Fix: 63309218
Test: make RunSettingsRoboTests