Ensure CI tests include the hosts used for building release artifacts

[alilleybrinker]

We use cargo-dist to build release artifacts when it's time to cut new versions of our crates, but currently don't test in our regular CI testing on the same hosts. In particular, we always target -latest versions for test hosts, which release build hosts do not.

There's some complexity here, as cargo-dist computes the runners to target based on the user's configuration and other considerations, but we can look at the output of prior releases, see what was used, and try to match it in testing. It may be that there's a better way, but this will at least work.