docs: update kowk nodepool example

[helen-frank]

Fixes #N/A

Description
update kowk nodepool example, the current example will not work properly due to the change of #1497.

❯ cat <<EOF | envsubst | kubectl apply -f -
apiVersion: karpenter.sh/v1
kind: NodePool
metadata:
  name: default
spec:
  template:
    spec:
      requirements:
        - key: kubernetes.io/arch
          operator: In
          values: ["amd64"]
        - key: kubernetes.io/os
          operator: In
          values: ["linux"]
        - key: karpenter.sh/capacity-type
          operator: In
          values: ["spot"]
      nodeClassRef:
        name: default
        kind: KWOKNodeClass
        group: karpenter.kwok.sh
      expireAfter: 720h # 30 * 24h = 720h
  limits:
    cpu: 1000
  disruption:
    consolidationPolicy: WhenUnderutilized
---
apiVersion: karpenter.kwok.sh/v1alpha1
kind: KWOKNodeClass
metadata:
  name: default
EOF
kwoknodeclass.karpenter.kwok.sh/default created
The NodePool "default" is invalid: 
* spec.disruption.consolidationPolicy: Unsupported value: "WhenUnderutilized": supported values: "WhenEmpty", "WhenEmptyOrUnderutilized"
* spec.disruption.consolidateAfter: Required value
* <nil>: Invalid value: "null": some validation rules were not checked because the object was invalid; correct the existing errors to complete validation

How was this change tested?

❯ cat <<EOF | envsubst | kubectl apply -f -
apiVersion: karpenter.sh/v1
kind: NodePool
metadata:
  name: default
spec:
  template:
    spec:
      requirements:
        - key: kubernetes.io/arch
          operator: In
          values: ["amd64"]
        - key: kubernetes.io/os
          operator: In
          values: ["linux"]
        - key: karpenter.sh/capacity-type
          operator: In
          values: ["spot"]
      nodeClassRef:
        name: default
        kind: KWOKNodeClass
        group: karpenter.kwok.sh
      expireAfter: 720h # 30 * 24h = 720h
  limits:
    cpu: 1000
  disruption:
    consolidationPolicy: WhenEmptyOrUnderutilized
    consolidateAfter: 10s
---
apiVersion: karpenter.kwok.sh/v1alpha1
kind: KWOKNodeClass
metadata:
  name: default
EOF
nodepool.karpenter.sh/default created
kwoknodeclass.karpenter.kwok.sh/default created

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[coveralls]

Pull Request Test Coverage Report for Build 10492400175

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 7 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.06%) to 77.766%

---

Files with Coverage Reduction	New Missed Lines	%
pkg/controllers/provisioning/scheduling/preferences.go	7	86.67%

Totals
Change from base Build 10476497233:	-0.06%
Covered Lines:	8912
Relevant Lines:	11460

---

💛 - Coveralls

[jonathan-innis]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: helen-frank, jonathan-innis

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