Bump org.springframework.kafka:spring-kafka-bom from 3.3.14 to 3.3.15

Bumps [org.springframework.kafka:spring-kafka-bom](https://github.com/spring-projects/spring-kafka) from 3.3.14 to 3.3.15.
- [Release notes](https://github.com/spring-projects/spring-kafka/releases)
- [Commits](spring-projects/spring-kafka@v3.3.14...v3.3.15)

---
updated-dependencies:
- dependency-name: org.springframework.kafka:spring-kafka-bom
  dependency-version: 3.3.15
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

build.gradle

@@ -103,7 +103,7 @@ ext {
     springAmqpVersion = '3.2.9'
     springDataVersion = '2025.0.11'
     springGraphqlVersion = '1.4.5'
-    springKafkaVersion = '3.3.14'
+    springKafkaVersion = '3.3.15'
     springRetryVersion = '2.0.12'
     springSecurityVersion = '6.5.9'
     springVersion = '6.2.18'