Ip address should not be a part of the DatanodeID since it can change

The DatanodeID identified by the DatanodeDetails object is persisted to disk and read back on restart. The following fields are currently being serialized and we should omit ip address from this set.

UUID uuid;
String ipAddress;
String hostName;
List<Port> ports;
String certSerialId;

cc: arpaga this is follow-up from HDDS-1473