[CORE-106517] Fix outdated config in the sample (#83)

config/samples/banzaicloud_v1beta1_kafkacluster.yaml

@@ -55,13 +55,13 @@ spec:
   #	alerts with 'rollingupgrade'
   #  failureThreshold: 1
 
-  # concurrentBrokerRestartsAllowed controls how many brokers can be restarted in parallel during a rolling upgrade. If
+  # concurrentBrokerRestartCountPerRack controls how many brokers can be restarted in parallel during a rolling upgrade. If
   # it is set to a value greater than 1, the operator will restart up to that amount of brokers in parallel, if the
   # brokers are within the same AZ (as specified by "broker.rack" in broker read-only configs). Since using Kafka broker
   # racks spreads out the replicas, we know that restarting multiple brokers in the same rack will not cause more than
   # 1/Nth of the replicas of a topic-partition to be unavailable at the same time, where N is the number of racks used.
   # This is a safe way to speed up the rolling upgrade.
-  #  concurrentBrokerRestartsAllowed: 1
+  #  concurrentBrokerRestartCountPerRack: 1
 
   # brokerConfigGroups specifies multiple broker configs with unique name
   brokerConfigGroups: