Bump plugin.spring from 1.9.23 to 2.0.20

Bumps [plugin.spring](https://github.com/JetBrains/kotlin) from 1.9.23 to 2.0.20.
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/v2.0.20/ChangeLog.md)
- [Commits](JetBrains/kotlin@v1.9.23...v2.0.20)

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

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

build.gradle.kts

@@ -5,7 +5,7 @@ plugins {
     id("io.spring.dependency-management") version "1.1.6"
     id("io.gitlab.arturbosch.detekt") version "1.23.6"
     kotlin("jvm") version "1.9.23"
-    kotlin("plugin.spring") version "1.9.23"
+    kotlin("plugin.spring") version "2.0.20"
 }
 
 group = "no.nav.syfo"