[native] Hit new_thread endpoint in CommunityConfiguration

Summary:
Hit new_thread endpoint and create new community when "Create community" button is pressed in CommunityConfiguration.

Handling of loading state + error message will be handled in subsequent diff.

Depends on D7968

Test Plan:
Works as expected, can observe that communities are created:

Reviewers: ashoat, ginsu

Reviewed By: ashoat

Subscribers: tomek

Differential Revision: https://phab.comm.dev/D7978