add cgroup v1 warning as it is in maintaince mode for kube

[pacoxu]

• add a warning if the node is cgroup v1

The v1.31 KEP https://github.com/kubernetes/enhancements/issues/4569

• https://github.com/kubernetes/enhancements/blob/master/keps/sig-node/4569-cgroup-v1-maintenance-mode/README.md KEP-4569: Moving cgroup v1 support into maintenance mode

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: neolit123, pacoxu

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