[lib][native] Remove displayFailureAlert prop from *EditUserAvatarProvider

Summary:
As of D8341 we no longer use or need this prop. Surfacing of errors is handled by platform-specific code for consistency.

Now we just need to get rid of useUploadSelectedMedia and we can consolidate NativeEditUserAvatarProvider, WebEditUserAvatarProvider, and BaseEditUserAvatarProvider into a single platform-agnostic EditUserAvatarProvider.

Depends on D8341

Test Plan: NA/flow/eslint

Reviewers: ashoat, ginsu, rohan

Reviewed By: ashoat

Subscribers: tomek

Differential Revision: https://phab.comm.dev/D8342