Bump kafka-clients from 2.8.0 to 3.0.0 in /examples

Bumps kafka-clients from 2.8.0 to 3.0.0.

---
updated-dependencies:
- dependency-name: org.apache.kafka:kafka-clients
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

examples/kafka-cluster/build.gradle

@@ -10,7 +10,7 @@ dependencies {
     testCompileOnly "org.projectlombok:lombok:1.18.20"
     testAnnotationProcessor "org.projectlombok:lombok:1.18.10"
     testImplementation 'org.testcontainers:kafka'
-    testImplementation 'org.apache.kafka:kafka-clients:2.8.0'
+    testImplementation 'org.apache.kafka:kafka-clients:3.0.0'
     testImplementation 'org.assertj:assertj-core:3.20.2'
     testImplementation 'com.google.guava:guava:23.0'
     testImplementation 'org.slf4j:slf4j-simple:1.7.32'