ForEachElement breaks LG

[EricDahlvang]

@gabog discovered 4.15.1-rc0 will break existing bots. Greeting LG is not found.

Discussed with Carlos, and he mentioned the Services are probably not copied to the new child context and provided this fix:

                if (dc.Services != null)
                {
                    foreach (var service in dc.Services)
                    {
                        childDc.Services[service.Key] = service.Value;
                    }
                }