how do i use the correct node version in gh actions?

✅SolvedDeploying

Trying to deploy a new version of a Wasp 0.20.1 app to Coolify. Deployments worked fine for a while, but I most recently tried to deploy a new version with some changes and I got some sort of type error (only on GH actions, I think it was using a diff version of some deps? I updated local deps and then was able to get the error in dev. Not something I changed, so I didn't attempt to fix it). I figured I might as well update, and so I incrementally updated to 0.20.1. All runs fine in dev, but when I push to github it fails in CI saying my node version is wrong. How do I update it to use the right version?