Bump org.springframework.kafka:spring-kafka-bom from 3.1.7 to 3.1.8

Bumps [org.springframework.kafka:spring-kafka-bom](https://github.com/spring-projects/spring-kafka) from 3.1.7 to 3.1.8.
- [Release notes](https://github.com/spring-projects/spring-kafka/releases)
- [Commits](spring-projects/spring-kafka@v3.1.7...v3.1.8)

---
updated-dependencies:
- dependency-name: org.springframework.kafka:spring-kafka-bom
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

build.gradle

@@ -111,7 +111,7 @@ ext {
     springAmqpVersion = '3.1.6'
     springDataVersion = '2023.1.9'
     springGraphqlVersion = '1.2.8'
-    springKafkaVersion = '3.1.7'
+    springKafkaVersion = '3.1.8'
     springRetryVersion = '2.0.8'
     springSecurityVersion = '6.2.6'
     springVersion = '6.1.12'