[lib][native] Stop persisting connection

Summary:
issue: https://linear.app/comm/issue/ENG-4460/refactor-connection-field
After D9018 there is no need to persist connection field, since we change it back to the default value on rehydrate action anyway. Now we won't be persisting it, so we also won't have the
need to be changing it on rehydrate action.

Test Plan:
Checked that connection is not getting rehydrated, chceked that after @@INIT action the state of connection is equal to the dafault value.
Checked that the sub state for key connection` modified, skipping.` warning is gone

Reviewers: michal, kamil

Reviewed By: michal

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D9020