chore(deps): bump plugin.serialization from 2.2.20 to 2.2.21

Bumps [plugin.serialization](https://github.com/JetBrains/kotlin) from 2.2.20 to 2.2.21.
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/v2.2.21/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.2.20...v2.2.21)

---
updated-dependencies:
- dependency-name: plugin.serialization
  dependency-version: 2.2.21
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

build.gradle.kts

@@ -11,7 +11,7 @@ plugins {
     alias(libs.plugins.changelog) // Gradle Changelog Plugin
     alias(libs.plugins.qodana) // Gradle Qodana Plugin
     alias(libs.plugins.kover) // Gradle Kover Plugin
-    kotlin("plugin.serialization") version "2.2.20"
+    kotlin("plugin.serialization") version "2.2.21"
 }
 
 group = providers.gradleProperty("pluginGroup").get()