Add link to the issue

Author: rmk135

tests/unit/providers/test_configuration_py2_py3.py

@@ -417,6 +417,7 @@ def test_double_override(self):
         self.assertEqual(services.value_getter(), 'services2')
 
     def test_reset_overriding_cache(self):
+        # See: https://github.com/ets-labs/python-dependency-injector/issues/428
         class Core(containers.DeclarativeContainer):
             config = providers.Configuration()
 
@@ -443,6 +444,7 @@ class Application(containers.DeclarativeContainer):
         self.assertEqual(container.core.greetings(), 'Hello Bob')
 
     def test_reset_overriding_cache_for_option(self):
+        # See: https://github.com/ets-labs/python-dependency-injector/issues/428
         class Core(containers.DeclarativeContainer):
             config = providers.Configuration()