[ISSUE #21] Distinguish between brokerName and brokerClusterName (#22)

diff --git a/pkg/controller/broker/broker_controller.go b/pkg/controller/broker/broker_controller.go
index b3e6cf6..6c22dcc 100644
--- a/pkg/controller/broker/broker_controller.go
+++ b/pkg/controller/broker/broker_controller.go
@@ -406,7 +406,7 @@
 							Value: strconv.Itoa(replicaIndex),
 						}, {
 							Name:  cons.EnvBrokerClusterName,
-							Value: broker.Name + "-" + strconv.Itoa(brokerGroupIndex),
+							Value: broker.Name,
 						}, {
 							Name:  cons.EnvBrokerName,
 							Value: broker.Name + "-" + strconv.Itoa(brokerGroupIndex),