CLI: Rollback some versions for node 18 compatibility

[josephjclark]

Rolling back a couple of versions for node 18 compatibility.

This is needed for github sync, which uses node 18 in the actions. We need to do something about that.

I've also restored the node 18 integration tests, as we clearly need them still

Fixes #1324 (sort of)

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[josephjclark]

All tests here break in node 18, both locally and in CI.

Same on main.

Not going to worry about this if it's not free because we shouldn't be in this state for very long.

I have run a node18 pull with openfnx and it worked fine - that'll have to be good enough