fix: use get_user_model() for E5102 imported-auth-user

Don't import django.contrib.auth.models.User model. Use
django.contrib.auth.get_user_model() instead.

36ea72b37c/pylint_django/checkers/auth_user.py (L18-L22)

common/djangoapps/entitlements/management/commands/expire_and_create_entitlements.py

@@ -9,12 +9,14 @@ from math import ceil
 from textwrap import dedent
 
 from django.core.management import BaseCommand
-from django.contrib.auth.models import User
+from django.contrib.auth import get_user_model
 from common.djangoapps.entitlements.tasks import expire_and_create_entitlements
 from common.djangoapps.entitlements.models import CourseEntitlement
 
 logger = logging.getLogger(__name__)  # pylint: disable=invalid-name
 
+User = get_user_model()
+
 #course uuids for which entitlements should be expired after 18 months.
 MIT_SUPPLY_CHAIN_COURSES = [
     '0d9b47982e3d486aa3189a7035bbda77',