skip relevant tests if keys have expired
we hardcode the expiry date for now, because we have a chicken and egg problem: to load the expiry dates, we need a working GPG library, and we are not so strong with expiration parsing yet, especially since there can be many expiration dates buried in subkeys, which I'm not confident we can parse. furthermore, the proper solution here is to remove expired keys from the test suite, but that is difficult for keys such as zack's that have very peculiar confugs. this allows us to re-enable tests in build as reproducible builds should just skip those tests now. it is useful to run tests in builds because it makes sure we run the test suite within the build environment. even though we run tests in the release process, that can be forgotten and may run in a different environment.