Kafka Producer zipkin reporter is not initialized

In Kafka Producer sample, zipkin reporter is not initialized, hence tracings are not reported to the zipkin consumer.
openfeign sample works fine.

Inspect the Kafka Producer sample's initialization entry point and compare it with the working OpenFeign sample. Trace the reporter setup through the sample, then verify that produced messages generate traces visible in the Zipkin consumer.

Written by the indexing model from the issue text.