Updated test URL patterns to use path() and re_path().

tests/auth_tests/urls_custom_user_admin.py

@@ -1,7 +1,7 @@
-from django.conf.urls import url
 from django.contrib import admin
 from django.contrib.auth import get_user_model
 from django.contrib.auth.admin import UserAdmin
+from django.urls import path
 
 site = admin.AdminSite(name='custom_user_admin')
 
@@ -19,5 +19,5 @@ class CustomUserAdmin(UserAdmin):
 site.register(get_user_model(), CustomUserAdmin)
 
 urlpatterns = [
-    url(r'^admin/', site.urls),
+    path('admin/', site.urls),
 ]