Bump jvm from 2.1.20 to 2.1.21 in the prod-dependencies group

Bumps the prod-dependencies group with 1 update: [jvm](https://github.com/JetBrains/kotlin).


Updates `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: jvm
  dependency-version: 2.1.21
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: prod-dependencies
...

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

Author: dependabot[bot]

build.gradle.kts

@@ -2,7 +2,7 @@ import org.gradle.api.tasks.testing.logging.TestExceptionFormat
 import org.gradle.api.tasks.testing.logging.TestLogEvent
 
 plugins {
-    kotlin("jvm") version "2.1.20"
+    kotlin("jvm") version "2.1.21"
     id("org.jlleitschuh.gradle.ktlint") version "12.2.0"
     id("org.jetbrains.kotlinx.kover") version "0.9.1"
 }