Changes to List contacts

added subschema #1 subschema #2 to the errors/items response property oneOf list for the response status 403

the errors/items response's property type changed from object to no type for status 403

removed the required property errors/items/code from the response with the 403 status

removed the required property errors/items/title from the response with the 403 status

removed the optional property errors/items/message from the response with the 403 status