NIFI-13489 Remove Kafka 2.6 Processors

[exceptionfactory]

Summary

NIFI-13489 Removes the Kafka 2.6 Processors in the nifi-kafa-2-6-nar module.

NiFi 2.0.0-M4 included redesigned processors ConsumeKafka and PublishKafka supporting Kafka 3 through a decoupled Controller Service interface, implemented under NIFI-11259. Any feature gaps or issues should be addressed to these new components based on current supported versions of Kafka client libraries.

Tracking

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Issue Tracking

• [X] Apache NiFi Jira issue created

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• [X] Pull Request title starts with Apache NiFi Jira issue number, such as NIFI-00000
• [X] Pull Request commit message starts with Apache NiFi Jira issue number, as such NIFI-00000

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Build

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  • [X] JDK 21

Licensing

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[joewitt]

This is a thorough update thank. Builds on paul's good work to move to a more sustaininable model.

It is not nice that it means users need to update their flows for sure. But frankly we've had to cause that with each major Kafka update. The new model should give us a better go forward strategy.

Lets see if other feedback comes in. Meanwhile full clean build is good. Running full ci suite as we speak.