Fix Helm chart to support clustered Zookeepers (#3611)

Author: nicknezis

deploy/kubernetes/helm/templates/zookeeper.yaml

@@ -118,6 +118,10 @@ spec:
           value: "{{ .Values.zookeeper.serverPort }}"
         - name: ZK_ELECTION_PORT
           value: "{{ .Values.zookeeper.leaderElectionPort }}"
+        - name: ZOOKEEPER_SERVERS
+          {{- $replicaCount := int .Values.zkReplicas }}
+          {{- $fullName := printf "%s-%s" .Release.Name "zookeeper" }}
+          value: "{{ range $i, $e := until $replicaCount }}{{ fullName }}-{{ $e }},{{ end }}"
         command:
         - sh
         - -c