Upgrading Kotlin exercises

I tried opening an MR to improve a Kotlin exercise (most of them use an old JUnit).
I was then redirected here after the issue was auto-closed in GitHub.
I want to improve the exercises and help create the Kotlin test runner but after reading the blog post, it’s still unclear to me how can I be part of Exercism and become a maintainer. Thank you.

Welcome!

Thank you for your attempt to contribute. I’ve re-opened the PR and commented on it here: update gradle and junit by lsoares · Pull Request #557 · exercism/kotlin · GitHub.

I am not a Kotlin maintainer as I no longer use Kotlin in production at work, but I am happy to discuss this with you and make sure it can be merged, etc.