coverage: Add test for REST requests to /json API unauthed.

zerver/lib/rest.py

@@ -104,6 +104,7 @@ def rest_dispatch(request, **kwargs):
             # If this looks like a request from a top-level page in a
             # browser, send the user to the login page
             if 'text/html' in request.META.get('HTTP_ACCEPT', ''):
+                # TODO: It seems like the `?next=` part is unlikely to be helpful
                 return HttpResponseRedirect('%s/?next=%s' % (settings.HOME_NOT_LOGGED_IN, request.path))
             # Ask for basic auth (email:apiKey)
             elif request.path.startswith("/api"):