RoleRequiredRoleModelMixin Generates Migrations with blank=True, null=True

[whitej6]

Environment

• Nautobot version (Docker tag too if applicable): 2.0.0a1
• Python version: 3.8
• Database platform, version: postgres
• Middleware(s):

Steps to Reproduce

1. Create model with RoleRequiredRoleModelMixin
2. Run makemigrations

Expected Behavior

blank=False, null=False in the migration

Observed Behavior

blank=True, null=True in the migration

[jathanism]

It looks like the nomenclature and assertions here need to be fixed:

https://github.com/nautobot/nautobot/blob/next/nautobot/extras/models/roles.py#L45-L64

1. RoleModelMixin is calling RoleField() with no arguments. This should be the "required" version and should explicitly call RoleField(null=True, blank=True).
2. RoleRequiredModelMixin is subclassing RoleModelMixin and instead should just also inherit from models.Model similar to RoleModelMixin, and should not be calling RoleField(null=False, blank=False).

It appears the naming is backward here and the inheritance should not be done in this way.

[glennmatthews]

Implemented in #3301.