Action to show that you can create an action without an action.yml file. Publishing to the marketplace requires an action.yml file, but can be removed after publishing. Publishing a new version is not possibe then, without an action.yml file 😢.
The runner does not care about the marketplace, and just looks at the action repo for action.yml, action.yaml, Dockerfile, or dockerfile in the root of the repository or folder that you are executing.
