[BUG] nodeMetric and podsMetric in NodeMtric are empty

[jasonliu747]

What happened:
After updating to the latest code, nodeMetric and podsMetric in NodeMetric became empty.

jason@B-54R0MD6R-0116 ~ % kubectl get nodemetrics.slo.koordinator.sh cn-hangzhou.192.168.0.35 -o yaml
apiVersion: slo.koordinator.sh/v1alpha1
kind: NodeMetric
metadata:
  creationTimestamp: "2022-07-21T06:28:02Z"
  generation: 1
  name: cn-hangzhou.192.168.0.35
  resourceVersion: "42125969"
  uid: 6b464015-53f0-4280-83c8-d33eb5349525
spec: {}
status:
  nodeMetric:
    nodeUsage: {}
  podsMetric:
  - name: training-operator-6bfc7b8d86-rcdjc
    namespace: kubeflow
    podUsage: {}
  - name: kube-flannel-ds-6fdzc
    namespace: kube-system
    podUsage: {}
  - name: kube-proxy-worker-g9jc5
    namespace: kube-system
    podUsage: {}
  - name: node-exporter-gskjg
    namespace: arms-prom
    podUsage: {}
  - name: storage-operator-6dbbc4c97f-chpxc
    namespace: kube-system
    podUsage: {}
  - name: alicloud-monitor-controller-7f7c4898b7-mvblr
    namespace: kube-system
    podUsage: {}
  - name: koordlet-9ncn2
    namespace: koordinator-system
    podUsage: {}
  - name: kube-state-metrics-84b7694445-6cmw2
    namespace: arms-prom
    podUsage: {}
  - name: koord-scheduler-686bcf56d7-8sxgn
    namespace: koordinator-system
    podUsage: {}
  - name: metrics-server-96d9d8ff-rvfhk
    namespace: kube-system
    podUsage: {}
  - name: csi-plugin-2rblc
    namespace: kube-system
    podUsage: {}
  - name: csi-provisioner-5b8874b7cd-cgkqw
    namespace: kube-system
    podUsage: {}
  - name: ack-cost-exporter-84665744c6-gqnx5
    namespace: kube-system
    podUsage: {}
  - name: coredns-77c9587874-64g6h
    namespace: kube-system
    podUsage: {}
  - name: koord-manager-779cfccf7c-jnwr5
    namespace: koordinator-system
    podUsage: {}
  updateTime: "2022-07-21T06:42:27Z"

What you expected to happen:

How to reproduce it (as minimally and precisely as possible):

Anything else we need to know?:

Environment:

• App version: f32a0ba
• Kubernetes version (use kubectl version): v1.22.3
• Install details (e.g. helm install args):
• Others:

[jasonliu747]

/area koord-manager

[jasonliu747]

/assign
looks like it was introduced by #378

[jasonliu747]

For more info, please check: https://kubernetes.io/zh-cn/docs/tasks/extend-kubernetes/custom-resources/custom-resource-definitions/#field-pruning