Changes to Get schedule by id

the response property _status/messages/items/data became nullable for the status 400

the response property _status/messages/items/data became nullable for the status 404

the response property _status/messages/items/detail became nullable for the status 400

the response property _status/messages/items/detail became nullable for the status 404

the response property admin_key became nullable for the status 200

the response property creator_account_id became nullable for the status 200

the response property executed_timestamp became nullable for the status 200

the response property expiration_time became nullable for the status 200

the response property payer_account_id became nullable for the status 200

the response property schedule_id became nullable for the status 200