Bump org.jetbrains.kotlin.jvm from 1.9.20 to 1.9.21

Bumps [org.jetbrains.kotlin.jvm](https://github.com/JetBrains/kotlin) from 1.9.20 to 1.9.21.
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v1.9.20...v1.9.21)

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

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

build.gradle

@@ -7,7 +7,7 @@ import org.jetbrains.intellij.tasks.RunPluginVerifierTask
 plugins {
     id 'java'
     id 'org.jetbrains.intellij' version '1.16.0'
-    id("org.jetbrains.kotlin.jvm") version "1.9.20"
+    id("org.jetbrains.kotlin.jvm") version "1.9.21"
     id 'org.jetbrains.changelog' version '2.2.0'
     id 'org.jetbrains.qodana' version '0.1.13'
     id "io.freefair.lombok" version "8.4"