[1.8.x] Sorted imports with isort; refs #23860.

Backport of 0ed7d15563 from master

tests/urlpatterns_reverse/named_urls.py

@@ -1,8 +1,7 @@
-from django.conf.urls import url, include
+from django.conf.urls import include, url
 
 from .views import empty_view
 
-
 urlpatterns = [
     url(r'^$', empty_view, name="named-url1"),
     url(r'^extra/(?P<extra>\w+)/$', empty_view, name="named-url2"),