Bump kotlin.version from 1.9.10 to 1.9.21 (#1028)

Bumps `kotlin.version` from 1.9.10 to 1.9.21.

Updates `org.jetbrains.kotlin:kotlin-stdlib` from 1.9.10 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@v1.9.10...v1.9.21)

Updates `org.jetbrains.kotlin:kotlin-maven-plugin` from 1.9.10 to 1.9.21

---
updated-dependencies:
- dependency-name: org.jetbrains.kotlin:kotlin-stdlib
  dependency-type: direct:development
  update-type: version-update:semver-patch
- dependency-name: org.jetbrains.kotlin:kotlin-maven-plugin
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

pom.xml

@@ -52,7 +52,7 @@
 		<javac.target>1.8</javac.target>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 		<junit.version>5.10.1</junit.version>
-		<kotlin.version>1.9.10</kotlin.version>
+		<kotlin.version>1.9.21</kotlin.version>
 		<kotlin.compiler.incremental>true</kotlin.compiler.incremental>
 	</properties>