Bump kotlin from 1.9.25 to 2.0.20

Bumps `kotlin` from 1.9.25 to 2.0.20.

Updates `org.jetbrains.kotlin:kotlin-gradle-plugin` from 1.9.25 to 2.0.20
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v1.9.25...v2.0.20)

Updates `org.jetbrains.kotlin:kotlin-stdlib` from 1.9.25 to 2.0.20
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v1.9.25...v2.0.20)

Updates `org.jetbrains.kotlin.plugin.serialization` from 1.9.25 to 2.0.20
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v1.9.25...v2.0.20)

---
updated-dependencies:
- dependency-name: org.jetbrains.kotlin:kotlin-gradle-plugin
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: org.jetbrains.kotlin:kotlin-stdlib
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: org.jetbrains.kotlin.plugin.serialization
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

gradle/libs.versions.toml

@@ -15,7 +15,7 @@ dagger = "2.52"
 hamcrest = "2.2"
 jsonUnit = "3.4.1"
 jvm = "17"
-kotlin = "1.9.25"
+kotlin = "2.0.20"
 kotlinCoroutines = "1.8.1"
 ktlint = "1.3.1"
 ktlintGradle = "12.1.1"