build: bump org.jetbrains.kotlin:kotlin-gradle-plugin

Bumps [org.jetbrains.kotlin:kotlin-gradle-plugin](https://github.com/JetBrains/kotlin) from 2.4.20-Beta2 to 2.4.20-RC.
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/v2.4.20-RC/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.4.20-Beta2...v2.4.20-RC)

---
updated-dependencies:
- dependency-name: org.jetbrains.kotlin:kotlin-gradle-plugin
  dependency-version: 2.4.20-RC
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

buildSrc/build.gradle.kts

@@ -6,7 +6,7 @@ import org.jetbrains.kotlin.gradle.dsl.JvmTarget
 
 buildscript {
     configurations.classpath {
-        resolutionStrategy.force("org.jetbrains.kotlin:kotlin-gradle-plugin:2.4.20-Beta2")
+        resolutionStrategy.force("org.jetbrains.kotlin:kotlin-gradle-plugin:2.4.20-RC")
     }
 }
 
@@ -59,6 +59,6 @@ configurations.configureEach {
 
 dependencies {
     implementation("org.jetbrains.dokka:dokka-gradle-plugin:2.2.0")
-    implementation("org.jetbrains.kotlin:kotlin-gradle-plugin:2.4.20-Beta2")
+    implementation("org.jetbrains.kotlin:kotlin-gradle-plugin:2.4.20-RC")
     implementation("com.vanniktech:gradle-maven-publish-plugin:0.37.0")
 }