Updates an existing discovery session.
discovery.update "serialNumber=<value>", ["sessionName=<value>"], ["sessionType=<network|cloud|csv>"], ["locationName=<value>"], ["networkScope=value1[,value2][,valueN]]",["autoProvision=<true|false>"], ["accountSerialNumber=<value>"], ["runOnce=<true|false>"], ["interval=<value>"], ["intervalUnit=<hour|day>"]