[lib] Add action type to remove peer user

Summary:
Similiar to D12961, but for relyingOnAuthoritativeKeyserve = false.
Added new action type that removes user IDs from both userStore and auxUserStore.
The action is dispatched when a peer receives message about account deletion.

Depends on D12961

Test Plan: The same as D12961, but this time faked relyingOnAuthoritativeKeyserver = false by reversing conditions for this flag in reducers.

Reviewers: inka, kamil, tomek

Reviewed By: inka, kamil

Subscribers: ashoat

Differential Revision: https://phab.comm.dev/D12962