update readme

Author: source-c

README.adoc

@@ -8,8 +8,8 @@ NOTE: Still contains zookeeper as a dependency.
 
 Tries to be as lightweigh as possible thus depends only on
 
-- `org.apache.kafka/kafka_2.12 "3.0.0"`
-- `org.apache.kafka/kafka-clients "3.0.0"`
+- `org.apache.kafka/kafka_2.12 "3.1.0"`
+- `org.apache.kafka/kafka-clients "3.1.0"`
 - `org.apache.zookeeper/zookeeper "3.7.0"`
 
 but excluding `jms`,`jmx*` and logging.