chore: add ci status badge

Author: fredleger

src/asdf/README.md

@@ -1,6 +1,8 @@
 
 # asdf (asdf)
 
+[![CI - Test Features](https://github.com/hoverkraft-tech/devcontainers/actions/workflows/test.yaml/badge.svg)](https://github.com/hoverkraft-tech/devcontainers/actions/workflows/test.yaml)
+
 A feature to install asdf (after changes of 0.16.0 version)
 
 ## Example Usage