[native] improve user experience for remvoing an avatar
Summary:
This diff does two things to improve the user experince, 1. we change the copy from "Remove avatar" to "Clear avatar" and we exlcude this option too if the avatar is not set
Test Plan:
Please see the demo videos to see the changes I made
User avatar:
Thread avatar:
Reviewers: ashoat, atul
Reviewed By: ashoat
Subscribers: ashoat, tomek, atul
Differential Revision: https://phab.comm.dev/D7642