Should only provide stable releases

I've noticed that this plugin publishes all versions of the Clojure CLI, including the intermediate non-stable releases. Often these releases are made during testing and contain bugs and there might be days or weeks where the non-stable version is the "latest".

We do now publish a "latest stable" version at https://download.clojure.org/install/stable.properties. Seems like maybe from a scan of the files here you are grabbing all versions and you don't have any indicator of which versions are and aren't stable. I'd be happy to work with you on figuring out an answer for that if I'm understanding correctly.