Add option to configure action via env variables

[pavelzw]

There are scenarios where you want to set an option like cache: false globally for all invocations without needing to manually specify them.
For example when you use a self-hosted runner that doesn't have access to cache, you might want to set cache: false for all invocations.
Adding environment variables like SETUP_PIXI_CACHE: false could be a way to do this.