Bump org.mockito.kotlin:mockito-kotlin in /generators/kotlin/resources

Bumps [org.mockito.kotlin:mockito-kotlin](https://github.com/mockito/mockito-kotlin) from 5.4.0 to 6.3.0.
- [Release notes](https://github.com/mockito/mockito-kotlin/releases)
- [Commits](mockito/mockito-kotlin@5.4.0...v6.3.0)

---
updated-dependencies:
- dependency-name: org.mockito.kotlin:mockito-kotlin
  dependency-version: 6.3.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

generators/kotlin/resources/gradle/libs.versions.toml

@@ -1,4 +1,4 @@
 [libraries]
 kotlin = { module = 'org.jetbrains.kotlin:kotlin-bom', version = '1.9.25' }
 
-mockito-kotlin = { module = 'org.mockito.kotlin:mockito-kotlin', version = '5.4.0' }
+mockito-kotlin = { module = 'org.mockito.kotlin:mockito-kotlin', version = '6.3.0' }