Changes to Update a contact list

added the new optional request property public_description

added the new optional request property subscriber_description

the request property name became optional

added the non-success response with the status 429

added the optional property subscriber_description to the response with the 200 status

added the optional property public_description to the response with the 200 status

added the optional property subscribed_contacts_count to the response with the 200 status

added the optional property unsubscribed_contacts_count to the response with the 200 status

added the media type application/json for the response with the status 403

endpoint added