Handle client response to initial notifications encrypted message request
Summary: This differential handles client response to initial notifications encrypted message request by creating new olm session for notifs.
Test Plan:
- Log out.
- Comment the code in log in panel that creates olm session for notifs.
- Log in.
- Query select * from olm_sessions and ensure there is a new entry for notifs
Reviewers: tomek, atul, bartek
Reviewed By: tomek, atul
Subscribers: ashoat
Differential Revision: https://phab.comm.dev/D7860