build(deps): bump rules_kotlin from 2.2.2-codeql.1 to 2.4.21

Bumps [rules_kotlin](https://github.com/bazel-contrib/rules_kotlin) from 2.2.2-codeql.1 to 2.4.21.
- [Release notes](https://github.com/bazel-contrib/rules_kotlin/releases)
- [Changelog](https://github.com/bazel-contrib/rules_kotlin/blob/master/CHANGELOG.md)
- [Commits](https://github.com/bazel-contrib/rules_kotlin/commits/v2.4.21)

---
updated-dependencies:
- dependency-name: rules_kotlin
  dependency-version: 2.4.21
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

MODULE.bazel

@@ -26,7 +26,7 @@ bazel_dep(name = "bazel_skylib", version = "1.9.0")
 bazel_dep(name = "abseil-cpp", version = "20260107.1", repo_name = "absl")
 bazel_dep(name = "nlohmann_json", version = "3.12.0.bcr.1", repo_name = "json")
 bazel_dep(name = "fmt", version = "12.1.0-codeql.1")
-bazel_dep(name = "rules_kotlin", version = "2.2.2-codeql.1")
+bazel_dep(name = "rules_kotlin", version = "2.4.21")
 bazel_dep(name = "gazelle", version = "0.54.0")
 bazel_dep(name = "rules_dotnet", version = "0.21.5-codeql.1")
 bazel_dep(name = "googletest", version = "1.18.0.bcr.1")