Now Magnum is not deploying any service or workload on k8s
worker nodes which need to get credentials from local to talk
to Magnum control plane. So the cloud-config file should be
removed from worker nodes to reduce the attach surface from
a security point of view.
Task: 40791
Story: 2008090
Change-Id: I72e418491cbd19291527bbe4b504d599c740fea9