Upgrade Apache Kafka to current stable version 2.0.1.
Issues have been observed with legacy Kafka producer being used in
notification engine together with newer Kafka broker versions.
Following changes are included:
* Deprecated configuration option `advertised.host.name` is replaced
with `listeners`.
* Default `log4j.properties` is used.
Story: 2005624
Task: 30933
Change-Id: I898b511b2ab8f68e4850faab2098044cd3f94ee7
dfd9423526