Fix Django 3.1 deprecation removal problems

- FieldDoesNotExist now has to be imported from django.core.exceptions
- Django docs specifically say not to import
  django.conf.global_settings, which now has the side-effect of
  triggering one of the check errors

awx/api/filters.py

@@ -7,10 +7,9 @@ import json
 from functools import reduce
 
 # Django
-from django.core.exceptions import FieldError, ValidationError
+from django.core.exceptions import FieldError, ValidationError, FieldDoesNotExist
 from django.db import models
 from django.db.models import Q, CharField, IntegerField, BooleanField
-from django.db.models.fields import FieldDoesNotExist
 from django.db.models.fields.related import ForeignObjectRel, ManyToManyField, ForeignKey
 from django.contrib.contenttypes.models import ContentType
 from django.contrib.contenttypes.fields import GenericForeignKey

awx/api/generics.py

@@ -10,18 +10,18 @@ import urllib.parse
 
 # Django
 from django.conf import settings
+from django.contrib.auth import views as auth_views
+from django.contrib.contenttypes.models import ContentType
 from django.core.cache import cache
+from django.core.exceptions import FieldDoesNotExist
 from django.db import connection
-from django.db.models.fields import FieldDoesNotExist
 from django.db.models.fields.related import OneToOneRel
 from django.http import QueryDict
 from django.shortcuts import get_object_or_404
 from django.template.loader import render_to_string
 from django.utils.encoding import smart_str
 from django.utils.safestring import mark_safe
-from django.contrib.contenttypes.models import ContentType
 from django.utils.translation import gettext_lazy as _
-from django.contrib.auth import views as auth_views
 
 # Django REST Framework
 from rest_framework.exceptions import PermissionDenied, AuthenticationFailed, ParseError, NotAcceptable, UnsupportedMediaType