Add comment for rebalance delay

execution/infrastructure/kafka/values.yaml

@@ -55,7 +55,8 @@ cp-kafka:
     # "min.insync.replicas": 2
     "auto.create.topics.enable": false
     "log.retention.ms": "10000" # 10s
-    #"log.retention.ms": "86400000" # 24h
+    # "log.retention.ms": "86400000" # 24h
+    # "group.initial.rebalance.delay.ms": "30000" # 30s
     "metrics.sample.window.ms": "5000" #5s
 
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