Create reusable action(s) for working with Batch

[natemcintosh]

Goal

(Discuss) making some of the more complex workflows in this repo into reusable actions that can be used in other places.

Context

PR #67 makes some really amazing progress for our ability to interact with Azure Batch from Github. We're very likely to re-use it in other places. It would be really nice to be able to use it as a reusable action, and not have to copy and paste it.

Questions

1. How does one even create a Github Action?
2. Would we have to create a new repo for such an action?
3. Would such an action be worth creating?

[natemcintosh]

Adding people I think might be interested: @zsusswein @jkislin @gvegayon

[zsusswein]

Will come back with thoughts. In the meantime linking

• Preview pkgdown in PR #52 which is based on some @gvegayon actions wizardry and would similarly benefit
• George's request on the above to make it sharable thing
• George's cfa-actions repo which has an open PR to add the above

[gvegayon]

And here is the first look into the action: https://github.com/CDCgov/cfa-actions/tree/first-commit/post-artifact. Need to finalize addressing @dylanhmorris's comments but merge is close!