chore: k8s_setup.sh should use kubectl wait

It's been over 5 years since the current logic to wait on clusters was contributed. Better to use `kubectl wait` now. This will also better convey failure when `kubectl` is not a valid binary.

Signed-off-by: Brennan Kinney <5098581+polarathene@users.noreply.github.com>

Author: polarathene

build/kubernetes/k8s_setup.sh

@@ -11,20 +11,17 @@ curl -Lo ./kind https://github.com/kubernetes-sigs/kind/releases/download/${KIND
 kind create cluster --image kindest/node:${K8S_VERSION}
 
 # Wait for cluster to be ready
-JSONPATH='{range .items[*]}{@.metadata.name}:{range @.status.conditions[*]}{@.type}={@.status};{end}{end}';
-until kubectl get nodes -o jsonpath="$JSONPATH" 2>&1 | grep -q "Ready=True"; do
-  sleep 1;
-done
+kubectl wait --for=condition=Ready nodes --all --timeout=60s >/dev/null 2>&1
 
 # Scale the CoreDNS replicas to simplify testing
 kubectl scale -n kube-system deployment/coredns --replicas=1
 
 # Patch CoreDNS deployment to use local coredns image
-kubectl patch deployment coredns -n kube-system -p "$(cat ~/go/src/${CIRCLE_PROJECT_USERNAME}/ci/build/kubernetes/coredns_deployment_patch.yaml)"
+kubectl patch deployment coredns -n kube-system -p "$(cat "~/go/src/${CIRCLE_PROJECT_USERNAME}/ci/build/kubernetes/coredns_deployment_patch.yaml")"
 
 # Patch CoreDNS clusterRoles to allow list/watch of EndpointSlice.
 # Remove this once EndpointSlice is part of the default CoreDNS clusterRoles.
-kubectl patch clusterroles system:coredns -n kube-system -p "$(cat ~/go/src/${CIRCLE_PROJECT_USERNAME}/ci/build/kubernetes/coredns_clusterroles_patch.yaml)"
+kubectl patch clusterroles system:coredns -n kube-system -p "$(cat "~/go/src/${CIRCLE_PROJECT_USERNAME}/ci/build/kubernetes/coredns_clusterroles_patch.yaml")"
 
 # Deploy test objects
-kubectl create -f ~/go/src/${CIRCLE_PROJECT_USERNAME}/ci/build/kubernetes/dns-test.yaml
+kubectl create -f "~/go/src/${CIRCLE_PROJECT_USERNAME}/ci/build/kubernetes/dns-test.yaml"