feat: list_forum_members-to-drf api to drf ( 14th )

[awais786]

issue

1. API is not DRF compatible.
2. Added new tests to verify all exceptions.
3. Added new test to verify JWT is working.

verify via postman

1: Try this URL with post request.
post-data = rolename: Group Moderator or any other role.

2: Valid data should be existed in admin/django_comment_common/role/ table.

expected result
{ "course_id": "course-v1:edx+cs222+2311", "Group Moderator": [ { "username": "login_service_user", "email": "[email protected]", "first_name": "", "last_name": "", "group_name": null } ], "division_scheme": "none" }

Verify from dashboard
1: Go to this page
2: User needs aleast two roles ( course-access-role as staff and Administrator as Forum Admin.

[feanil]

Instead of defaulting to True I think it's better to default to false and have a check for each of the combinations we're okay with. I'm having a little bit of trouble understanding how the two checks are different. If you're already checking to see if the user is a FORUM_ROLE_ADMINSTATOR do you care about whether or not that parameter is passed into the request?