Update dependency org.jetbrains.kotlin:kotlin-gradle-plugin to v2.3.20 (#485)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

gradle/libs.versions.toml

@@ -20,7 +20,7 @@ asm = "org.ow2.asm:asm:9.9.1"
 diffUtils = "io.github.java-diff-utils:java-diff-utils:4.16"
 picnic = "com.jakewharton.picnic:picnic:0.7.0"
 mordant = "com.github.ajalt.mordant:mordant:3.0.2"
-kotlinPlugin = "org.jetbrains.kotlin:kotlin-gradle-plugin:2.3.20-RC3"
+kotlinPlugin = "org.jetbrains.kotlin:kotlin-gradle-plugin:2.3.20"
 dokkaPlugin = "org.jetbrains.dokka:dokka-gradle-plugin:2.1.0"
 mavenPublishPlugin = "com.vanniktech:gradle-maven-publish-plugin:0.36.0"
 spotlessPlugin = "com.diffplug.spotless:spotless-plugin-gradle:8.3.0"