[Notification-service] Bump plugin.spring in /notification-service

Bumps [plugin.spring](https://github.com/JetBrains/kotlin) from 2.0.0 to 2.1.0.
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.0.0...v2.1.0)

---
updated-dependencies:
- dependency-name: plugin.spring
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

notification-service/build.gradle.kts

@@ -9,7 +9,7 @@ plugins {
 	id("org.owasp.dependencycheck") version "10.0.3"
 
 	kotlin("jvm") version "2.1.0"
-	kotlin("plugin.spring") version "2.0.0"
+	kotlin("plugin.spring") version "2.1.0"
 	kotlin("plugin.jpa") version "2.1.0"
 	jacoco
 }