[lib] make useJoinCommunity compatible with the auto join community handler

Summary:
This diff updates useJoinCommunity to be more agnostic so that this hook can be used for both invite links + auto join community handler

Depends on D12706

Test Plan: flow + confirmed that there were no regressions with the joining a community through accepitng an invite link user flow

Reviewers: ashoat, inka

Reviewed By: ashoat

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D12713