User roles
- automatically add newly created users to the client group
- add role validation for login
- change login URL from /login to /user-login (because /login is from the default django rest auth URL)
- add role field to user representation
- add astroid to requirements.txt [CHORES]
please review thx @wulanmantiri @glendaesutanto @muzakiazami @doanandreas18
Edited by Kefas Satrio Bangkit Solidedantyo