Fixing Kafka vulnerabilities

Updating the Kafka version to v3.9.1 are fixing CVE issues we have in production:

- CVE-2025-27817
- CVE-2025-27819
- CVE-2025-27818

Could you fix a patch for us with these changes?

Author: mjovanc

gradle/libs.versions.toml

@@ -1,6 +1,6 @@
 [versions]
 kotest = "6.0.0.M1"
-kafka = "3.9.0"
+kafka = "3.9.1"
 kotlin = "2.1.0"
 kotlinx-coroutines = "1.10.1"
 dokka = "2.0.0"