Update short description of Scala Steward

README.md

@@ -9,7 +9,8 @@
 [![Scala Steward badge](https://img.shields.io/badge/Scala_Steward-helping-blue.svg?style=flat&logo=data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAA4AAAAQCAMAAAARSr4IAAAAVFBMVEUAAACHjojlOy5NWlrKzcYRKjGFjIbp293YycuLa3pYY2LSqql4f3pCUFTgSjNodYRmcXUsPD/NTTbjRS+2jomhgnzNc223cGvZS0HaSD0XLjbaSjElhIr+AAAAAXRSTlMAQObYZgAAAHlJREFUCNdNyosOwyAIhWHAQS1Vt7a77/3fcxxdmv0xwmckutAR1nkm4ggbyEcg/wWmlGLDAA3oL50xi6fk5ffZ3E2E3QfZDCcCN2YtbEWZt+Drc6u6rlqv7Uk0LdKqqr5rk2UCRXOk0vmQKGfc94nOJyQjouF9H/wCc9gECEYfONoAAAAASUVORK5CYII=)](https://scala-steward.org)
 [![Docker Pulls](https://img.shields.io/docker/pulls/fthomas/scala-steward.svg?style=flat&color=blue)](https://hub.docker.com/r/fthomas/scala-steward/)
 
-Scala Steward is a bot that helps you keep your library dependencies, sbt plugins, and Scala and sbt versions up-to-date.
+Scala Steward is a bot that helps you keep your library dependencies and build plugins up-to-date.
+It works with [Maven](https://maven.apache.org/), [Mill](https://mill-build.com/), [sbt](https://www.scala-sbt.org/), and [Scala CLI](https://scala-cli.virtuslab.org/).
 
 See also the announcement blog post:
 [*Keep your projects up-to-date with Scala Steward*](https://www.scala-lang.org/blog/2019/07/10/announcing-scala-steward.html)