Make the output directories if not exists

[rajbos]

I've bumped into this now three times: when the output directory does not exists (which it will not when the user starts with this), the action just crashes. I think it is a nicer experience to just create the directory for them: they indicate a path already where the files will be written to, so why not just make the dir for them as well? This PR handles that.

[UlisesGascon]

I love the idea, @rajbos!

I will suggest to move this logic to an utility as it is used at least in two places in src/action.js. Also it will be easier to add unit tests later on (I can help you to mock fs methods if you need as Jest can be quite tricky)

Also it will be nice to handle recursive folders by using fs methods like mkdirSync('<the path>', {recursive: true}) and fs.existsSync(<PATH>). More context: https://joshtronic.com/2021/01/17/recursively-create-directories-with-nodejs/

Also you can use Sync methods (fs.exists vs fs.existsSync) in this case as we can block main thread as this is github action is more like an script than a I/O Service 👍

[UlisesGascon]

Solved conflicts in e1fec72

[rajbos]

Moved the mkdir code into the utils class. Not sure about the next step: do you want to add unit tests now or later? When now, I do need some help with the setup of overwriting the fs class then.

I'd expect some tests for short/long file paths (multiple layers deep or not) as well as tests for when the folder already exists and when not?

[UlisesGascon]

I can help you with the tests, I will add some commits to the PR :)

[UlisesGascon]

@rajbos I will merge this PR to the branch feat/create-directories and from that branch I will add the tests and create a new PR against main.

See #53