Gsoc 2023 about us screen migration to compose

[narendraanjana09]

Fixes #41

Changes :
Migrated fragment_about.xml to AboutScreen.kt in Compose

Previous UI:

New UI Screen recording:

https://github.com/AOSSIE-Org/Agora-Android/assets/60137237/458e829f-539f-4b54-918f-8387318bb32a

Appetize App Link
https://appetize.io/app/d7wqeezvl3ynuojmq2fgpxgow4?device=pixel4&osVersion=11.0&scale=75

[hackeramitkumar]

LGTM