In get_node_by_instance_uuid, an exception ComputeNodeNotFound
will be thrown if can't find a node through instance uuid.
But the exception information replaces the node name with
instance uuid, which is misleading, so we define a new exception.
Closes-Bug: #1832156
Change-Id: Ic6c44ae44da7c3b9a1c20e9b24a036063af266ba