Update default image tag

[RainbowMango]

What type of PR is this?

/kind cleanup

What this PR does / why we need it:

Updates and corrects the default image tag.

Which issue(s) this PR fixes:
Fixes #

Special notes for your reviewer:

The steps to run the quick start demo would be:

1. launch Karmada: hack/local-up-karmada.sh
2. switch to host cluster and apply dashboards:

export KUBECONFIG=${HOME}/.kube/karmada.config
kubectl config use-context karmada-host

kubectl apply -f artifacts/dashboard/karmada-dashboard-sa.yaml
kubectl apply -f artifacts/dashboard/karmada-dashboard-api.yaml
kubectl apply -f artifacts/dashboard/karmada-dashboard-web.yaml
kubectl apply -f artifacts/dashboard/karmada-dashboard-configmap.yaml

3. expose the dashboard port to host:

kubectl port-forward -n karmada-system services/karmada-dashboard-web --address 0.0.0.0 8000:8000

4. launch dashboard by http://<host-ip>:8000
5. get the token

export KUBECONFIG=${HOME}/.kube/karmada.config
kubectl config use-context karmada-apiserver
kubectl apply -f artifacts/dashboard/karmada-dashboard-sa.yaml
kubectl -n karmada-system get secret/karmada-dashboard-secret -ojsonpath='{.data.token}' | base64 -d && echo

Does this PR introduce a user-facing change?:

NONE

[warjiang]

/lgtm
/approve

[karmada-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: warjiang

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• OWNERS [warjiang]

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