Deprecate Kafka 2.0 plugin

[xiangfu0]

Since kafka is released 5 years, I'm considering to remove the support for Kafka 2.0 in the next release.

Any objections or anyone still using Kafka 2?

[xiangfu0]

#17602

[Jackie-Jiang]

@siddharthteotia @mcvsubbu @yupeng9 @chenboat @jadami10

[jadami10]

We use our own plugin, so this is fine.