[web] Hide EditUserAvatarMenu when userAvatarSaveInProgress

Summary:
Hide the EditUserAvatarMenu when userAvatarSaveInProgress. Matches behavior of native.

Personally don't like when elements disappear/reappear, so would've preferred graying it out/disabling it... but this is fine for now.

Depends on D8263

Test Plan: Works as expected.

Reviewers: ashoat, ginsu, rohan, inka, michal, kamil

Reviewed By: kamil

Subscribers: tomek

Differential Revision: https://phab.comm.dev/D8264