build: Setup repo with tests

[Robdel12]

What is this?

This PR adds tests to the action and then the inputs I realized I needed when testing. Testing is important 👍

[Robdel12]

@wwilsman yeah it is, and they have to be checked into the repo if you're doing anything with dependencies:

As an alternative to checking in your node_modules directory you can use a tool called zeit/ncc to compile your code and modules into one file used for distribution.

😬 https://help.github.com/en/actions/automating-your-workflow-with-github-actions/creating-a-javascript-action#commit-and-push-your-action-to-github