Merge pull request #4587 from k8s-infra-cherrypick-robot/cherry-pick-4584-to-release-1.12

[release-1.12] wait for cluster to be Ready before hitting API server

Author: k8s-ci-robot

Makefile

@@ -350,7 +350,7 @@ create-workload-cluster: $(ENVSUBST) $(KUBECTL) ## Create a workload cluster.
 	timeout --foreground 300 bash -c "while ! $(KUBECTL) get secrets | grep $(CLUSTER_NAME)-kubeconfig; do sleep 1; done"
 	# Get kubeconfig and store it locally.
 	$(KUBECTL) get secrets $(CLUSTER_NAME)-kubeconfig -o json | jq -r .data.value | base64 --decode > ./kubeconfig
-	timeout --foreground 600 bash -c "while ! $(KUBECTL) --kubeconfig=./kubeconfig get nodes | grep control-plane; do sleep 1; done"
+	$(KUBECTL) wait --for=condition=Ready --timeout=10m cluster "$(CLUSTER_NAME)"
 
 	@echo 'run "$(KUBECTL) --kubeconfig=./kubeconfig ..." to work with the new target cluster'