Fix drop tracking of aggregator drop_original metrics (#5632)

agent/agent.go

@@ -364,6 +364,8 @@ func (a *Agent) runAggregators(
 
 			if !dropOriginal {
 				dst <- metric
+			} else {
+				metric.Drop()
 			}
 		}
 		cancel()

docker-compose.yml

@@ -17,7 +17,7 @@ services:
       - KAFKA_ADVERTISED_HOST_NAME=localhost
       - KAFKA_ADVERTISED_PORT=9092
       - KAFKA_ZOOKEEPER_CONNECT=zookeeper:2181
-      - KAFKA_CREATE_TOPICS="test:1:1"
+      - KAFKA_OFFSETS_TOPIC_REPLICATION_FACTOR=1
       - JAVA_OPTS="-Xms256m -Xmx256m"
     ports:
       - "9092:9092"