Update kafka-client.version to v4 (release/3.0.x) (major)

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
org.apache.kafka:kafka_2.13	3.8.1 -> 4.0.0
org.apache.kafka:kafka-streams-test-utils	3.8.1 -> 4.0.0
org.apache.kafka:kafka-server-common	3.8.1 -> 4.0.0
org.apache.kafka:kafka-raft	3.8.1 -> 4.0.0
org.apache.kafka:kafka-metadata	3.8.1 -> 4.0.0
org.apache.kafka:kafka-streams	3.8.1 -> 4.0.0
org.apache.kafka:kafka-clients	3.8.1 -> 4.0.0

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