Bump kafkaVersion from 7.9.1-ce to 8.1.0-ce

Bumps `kafkaVersion` from 7.9.1-ce to 8.1.0-ce.

Updates `org.apache.kafka:kafka-clients` from 7.9.1-ce to 8.1.0-ce

Updates `org.apache.kafka:kafka-streams-test-utils` from 7.9.1-ce to 8.1.0-ce

---
updated-dependencies:
- dependency-name: org.apache.kafka:kafka-clients
  dependency-version: 8.1.0-ce
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: org.apache.kafka:kafka-streams-test-utils
  dependency-version: 8.1.0-ce
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

build.gradle.kts

@@ -24,7 +24,7 @@ val jar by tasks.getting(Jar::class) {
 
 val log4j2Versjon = "2.25.2"
 val prometheusVersion = "0.16.0"
-val kafkaVersion = "7.9.1-ce"
+val kafkaVersion = "8.1.0-ce"
 val ktorVersion = "3.3.1"
 dependencies {
     implementation(kotlin("stdlib"))