Bump jvm from 2.0.20 to 2.0.21 in /lib/kotlin

Bumps [jvm](https://github.com/JetBrains/kotlin) from 2.0.20 to 2.0.21.
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.0.20...v2.0.21)

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

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

lib/kotlin/settings.gradle.kts

@@ -18,7 +18,7 @@
  */
 pluginManagement {
     plugins {
-        kotlin("jvm") version "2.0.20"
+        kotlin("jvm") version "2.0.21"
         id("com.ncorti.ktfmt.gradle") version "0.20.1"
     }
 }