Merge branch 'bump-django-enumfields' into 'master'

Bump Python requirement django-enumfields to 2.1.1

See merge request !1239

requirements.txt

@@ -4,7 +4,7 @@ apistar==0.7.2
 git+https://gitlab.com/teklia/apistar.git#egg=apistar
 django-admin-hstore-widget==1.1.0
 django-cors-headers==3.7.0
-django-enumfields==2.0.0
+django-enumfields==2.1.1
 django-redis==4.12.1
 django-rq==2.4.0
 djangorestframework==3.12.2