remove listener class from zk in test

Author: maltesander

tests/templates/kuttl/smoke/20-install-zk.yaml.j2

@@ -7,9 +7,8 @@ spec:
   image:
     productVersion: "{{ test_scenario['values']['zookeeper'] }}"
     pullPolicy: IfNotPresent
-  clusterConfig:
-    listenerClass: {{ test_scenario['values']['listener-class'] }}
 {% if lookup('env', 'VECTOR_AGGREGATOR') %}
+  clusterConfig:
     vectorAggregatorConfigMapName: vector-aggregator-discovery
 {% endif %}
   servers: