fix(deps): update kotlin to v2.2.21

Author: renovate[bot]

README.md

@@ -15,7 +15,7 @@ It has the following details:
   - Kotlin DSL
   - Version Catalog (libs.versions.toml)
 <!-- renovate: datasource=maven depName=org.jetbrains.kotlin:kotlin-gradle-plugin -->
-- Kotlin `2.2.0`
+- Kotlin `2.2.21`
 <!-- renovate: datasource=maven depName=org.springframework.boot:spring-boot-gradle-plugin -->
 - Spring Boot `3.5.7`
 <!-- renovate: datasource=maven depName=io.gitlab.arturbosch.detekt:detekt-gradle-plugin -->

gradle/libs.versions.toml

@@ -10,7 +10,7 @@ j2html = "1.6.0"
 # plugin versions
 springBoot = "3.5.7"
 springGradleDependencyManagement = "1.1.7"
-kotlin = "2.1.21"
+kotlin = "2.2.21"
 detekt = "1.23.8"
 dokka = "2.0.0"