fix(deps): update kotlin monorepo to v2

Author: renovate[bot]

gradle/libs.versions.toml

@@ -5,7 +5,7 @@ micronaut-docs = "2.0.0"
 micronaut-test = "4.7.0"
 
 dokka = "1.9.20"
-kotlin = "1.9.25"
+kotlin = "2.1.20"
 managed-ktor = "2.3.13"
 mockito-kotlin = "2.2.0"
 typesafe-config = "1.4.3"