[lib] Check the timestamps when removing thread members

Summary:
Check the timestamp and don't remove members when the timestamp is more recent than the operation.

https://linear.app/comm/issue/ENG-9117/update-removemembersspec

Depends on D13220

Test Plan: Perform a couple of remove and add members operations and check if the membership and timestamps are correct.

Reviewers: kamil, inka

Reviewed By: inka

Subscribers: ashoat

Differential Revision: https://phab.comm.dev/D13233