Update payments/core.py

Co-authored-by: Hugo Osvaldo Barrera <hugo@barrera.io>

Author: Asif Saif Uddin

payments/core.py

@@ -131,7 +131,7 @@ def autocomplete_with_subscription(self, payment):
     def cancel_subscription(self, subscription):
         """
         Cancel subscription
-        Used by providers, that use provider initiated subscription workflow
+        Used by providers, that use provider initiated cancellation workflow
         """
         raise NotImplementedError()