python3: use std pathlib instead of pathlib2 (#41220)

tests/conftest.py

@@ -3,7 +3,10 @@ import copy
 import pytest
 import django_webtest
 from collections import namedtuple
-import pathlib2
+try:
+    import pathlib
+except ImportError:
+    import pathlib2 as pathlib
 
 from django.core.management import call_command
 from django.contrib.auth import get_user_model
@@ -12,7 +15,7 @@ from django_rbac.utils import get_ou_model
 
 User = get_user_model()
 OU = get_ou_model()
-TEST_DIR = pathlib2.Path(__file__).parent
+TEST_DIR = pathlib.Path(__file__).parent
 
 
 @pytest.fixture