Update django-rest-framework to v3.1.0 or later

setup.py

@@ -5,7 +5,7 @@
 
 
 install_requires = (
-    'djangorestframework>=3.0.5,<3.1',
+    'djangorestframework>=3.1.0,<3.2',
     'incuna_mail>=2.0.0,<4.0.0',
 )
 

user_management/api/tests/test_views.py

@@ -1,7 +1,6 @@
 import datetime
 import re
 from collections import OrderedDict
-from unittest import expectedFailure
 
 from django.contrib.auth import get_user_model
 from django.contrib.auth.hashers import check_password
@@ -326,9 +325,6 @@ def test_send_email(self):
         self.assertIn('auth/password_reset/confirm/', sent_mail.body)
         self.assertIn('https://', sent_mail.body)
 
-    # max_length is incorrectly missing from options, fixed in:
-    # https://github.com/tomchristie/django-rest-framework/commit/c8609ba652e1752e690c9e27e02b3531589d0c2c
-    @expectedFailure
     def test_options(self):
         """
         Ensure information about email field is included in options request.