Workflow templates recommending checkout@v2

[hectorsector]

The workflows in this course us checkout@v1, but I noticed the templates in the Actions tab now default to checkout@v2. We should probably update the recommendations in this course to follow suit.

[mattdavis0351]

Agreed.

We may also want to think of ways to handle this when further changes get made to actions we aren't in control of. I can see this getting out of hand as we maintain courses down the line.

One idea is to have a repo of our own actions and use those instead of "public" ones unless there is a reason to do so.