Bump org.jetbrains.kotlin.jvm from 2.1.20 to 2.1.21 in the kotlin group

Bumps the kotlin group with 1 update: [org.jetbrains.kotlin.jvm](https://github.com/JetBrains/kotlin).


Updates `org.jetbrains.kotlin.jvm` from 2.1.20 to 2.1.21
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.1.20...v2.1.21)

---
updated-dependencies:
- dependency-name: org.jetbrains.kotlin.jvm
  dependency-version: 2.1.21
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: kotlin
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

build.gradle.kts

@@ -11,7 +11,7 @@ plugins {
     // Java support
     id("java")
     // Kotlin support
-    id("org.jetbrains.kotlin.jvm") version "2.1.20"
+    id("org.jetbrains.kotlin.jvm") version "2.1.21"
     // Gradle IntelliJ Plugin
     id("org.jetbrains.intellij.platform") version "2.5.0"
     // Gradle Grammar-Kit Plugin