Test on more recent Django versions too

Author: PeterJCLaw

.circleci/config.yml

@@ -35,7 +35,7 @@ references:
     matrix:
       parameters:
         python-version: ["3.6", "3.7", "3.8", "3.9"]
-        django-version: ["2.2", "3.0", "3.1"]
+        django-version: ["2.2", "3.0", "3.1", "3.2", "4.0"]
 
 executors:
   python: