Replace chassis_id with chassis_uuid on Nodes

The commit https://review.openstack.org/#/c/57495/ introduced the
chassis_uuid attribute for Nodes in the Ironic API, this patch adjusts
the client to reflect that change.

Change-Id: Ia490fbe0bcf32fc474a3c74842003addc2a94e6d
Merge "Replace chassis_id with chassis_uuid on Nodes"