Add action mint

[zachmayer]

What problem or use case are you trying to solve?
There’s a good marketplace action called actionlint that identifies issues with GitHub actions yaml files

Describe the UX of the solution you'd like
New GitHub action running action lint on the various action yamls

Do you have thoughts on the technical implementation?
I ran action lint on a fork and found a few minor issues

Describe alternatives you've considered
Not doing it
Additional context