Update kotlin monorepo to v2.3.20

Author: renovate[bot]

gradle/libs.versions.toml

@@ -15,7 +15,7 @@ console-api = "v0.6.1"
 google-cloud-libraries-bom = "26.77.0"
 google-cloud-sql-postgres-socket-factory = "1.28.1"
 htmlunit = "4.21.0"
-kotlin = "2.3.10"
+kotlin = "2.3.20"
 log4j1 = "1.2.17"
 minio = "8.6.0"
 protovalidate = "1.1.1"