[native] Pass threadID of newly created community to CommunityCreationMembers

Summary:
We need this to hit changeThreadSettings endpoint.

Depends on D8115

Test Plan: Able to log value in CommunityCreationMembers to ensure we get it as expected.

Reviewers: ashoat, ginsu

Reviewed By: ashoat

Subscribers: tomek

Differential Revision: https://phab.comm.dev/D8122