I think this is fine, but why not stick with the active LTS for this?

I don't have a very strong opinion, but since it's just a runtime for development in a way here, I thought there was no reason to stick to anything too much 🙂

If the intention is to stick to LTS, it shouldn't have 18, it should have lts/* or lts/hydrogen :-)

more of an aside than anything else, but for reasons, I always prefer to specify the exact version -- x.y.z

but, I am fine with any of the above for this. will approve as is, but will approve any of these alternatives as well

There is no guarantee that CI will always work well with LTS, so I would just specify the major version here 😑 (As you know, the JS ecosystem grows too fast!)