change user_name still used as login and add display_name for dashboard view instead of username on login

backend/apps/operations/tests_karung_web.py

@@ -156,7 +156,7 @@ class KarungWebCombinedTests(TestCase):
 @override_settings(KARUNG_WEB_ADMIN_BASE_URL="http://karung.internal")
 class RequestKarungTests(TestCase):
     def setUp(self):
-        user = User.objects.create_user(user_login="tester", password="secret")
+        user = User.objects.create_user(user_name="tester", password="secret")
         site = Site.objects.create(site_name="Sukawarna", user=user)
         self.kandang1 = Kandang.objects.create(kandang_name="Kandang 1", site=site)
         self.kandang2 = Kandang.objects.create(kandang_name="Kandang 2", site=site)