Refactor OpenApi specification for user registration

[vladyslavyarets]

Overview

Due to new logic described in ticket #478. Now users registries during apartment registration by its cooperation admin. So, users already created and stores in the database. Due to this changes in payload required.

Payload example

{
  "user_id": 4
  "registration_token": "7b3a32f0-1326-11ed-b2e2-b51ca8f90a82",
  "email": "test@gmail.com",
  "password": "Passw0rd",
  "phone_number": 380501112233
}

Note: all fields required. user_id is a id which user got during apartment registration. registration_token is a token which generates during creating of invitation and adds to invitation email.

Tasks:

1. Change openApi specification due to payload describer above.
2. Stab the logic in the controller for happy path.

[vladyslavyarets]

Hey team! Please add your planning poker estimate with ZenHub @gendalf-fx @ystoikov @artmarchenko

[vladyslavyarets]

Done!