Fix deprecation warnings for Django 1.11 and Django 2.0.

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>

mayan/apps/permissions/tests/test_api.py

@@ -2,7 +2,7 @@ from __future__ import unicode_literals
 
 from django.contrib.auth import get_user_model
 from django.contrib.auth.models import Group
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 
 from rest_api.tests import BaseAPITestCase
 from user_management.tests.literals import (