The correct answer is actually so simple. You don’t need to checkout anything, neither do you have to resort to COMMIT_HASH hacks (which don’t work on Cedar stack). All you need to do is: git ls-remote <remote>
> git ls-remote heroku
ddaszxcewb585d3a3c00de816a197b14462791a3 HEAD
ddaszxcewb585d3a3c00de816a197b14462791a3 refs/heads/master