[refresh-token] clear authentication_classes for refresh token view

Author: alvinchow86

rest_framework_jwt/views.py

@@ -37,6 +37,7 @@ class RefreshJSONWebToken(APIView):
     """
     throttle_classes = ()
     permission_classes = ()
+    authentication_classes = ()
     parser_classes = (parsers.FormParser, parsers.JSONParser,)
     renderer_classes = (renderers.JSONRenderer,)
     serializer_class = RefreshJSONWebTokenSerializer