ci: update Actions

[ijlyttle]

fix #247

[ijlyttle]

@nathancday Hi Nate!

I've been "away" too long; thanks for keeping the pilot-light lit for the last while.

I propose to ask forgiveness, rather than permission, to merge a few PRs, like this one, that take care of upkeep-type matters. If you see any problems, post-facto, I'll work to fix them.

I think there are a few other upkeep tasks I'll want to address (e.g. #251, #183), but I'll seek your review on those (if you are so inclined).