Contacts - Empty State

[mattgle]

Description

We want to add an empty state in the contacts view for plug mobile

Design: https://www.figma.com/file/no61f8MMPQlPUIaXSX3zCn/Plug---Wallet?node-id=10654%3A7932

[alinasytnik]

[iOS] QA approved ✅

[kevin4476]

[Android] QA approved ✅