Since PRs seem to be much rarer than pushes to main, it makes more sense
to do it this way. Perhaps in the future, it would make sense to run it on
all pushes, but the question would be how PRs are handled.
This reverts commit 759d031a5f.
This was originally to solve some issues with builds during the
workspace refactor in #86
but this didn't end up being the root cause, so it may actually be
better to split these tasks again.