Update kotlin monorepo to v2.3.20

Author: renovate[bot]

gradle/libs.versions.toml

@@ -5,7 +5,7 @@ appcompat = "1.7.1"
 collection = "1.5.0"
 jetSec = "1.1.0"
 junit = "1.3.0"
-kotlin = "2.1.21"
+kotlin = "2.3.20"
 material = "1.13.0"
 mavenPublish = "0.34.0"
 runner = "1.7.0"