chore(deps): bump org.jetbrains.kotlin:kotlin-test-junit5 (#598)

Bumps [org.jetbrains.kotlin:kotlin-test-junit5](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:kotlin-test-junit5
  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>

build.gradle.kts

@@ -9,7 +9,7 @@ val mockWebServerVersion = "4.12.0"
 val jacksonVersion = "2.16.0"
 val nettyVersion = "4.1.101.Final"
 val junitJupiterVersion = "5.10.1"
-val kotlinVersion = "1.9.20"
+val kotlinVersion = "1.9.21"
 val freemarkerVersion = "2.3.32"
 val kotestVersion = "5.8.0"
 val bouncyCastleVersion = "1.70"