Update NodeJS

[CocoisBuggy]

NodeJS 18 is end of life. For me, this means the package is harder to get (I am on nixos) and work out configs for than for supported node versions.

There shouldn't be too much challenge in bringing us forward, but of course it's a bit of a pain for @vnugent who ultimately has to deploy the thing (Sorry, viet)

Unless someone has a good reason not to, I'll bring us forward one version at a time until we're up to date.

[CocoisBuggy]

Just rolling forward yields a pretty quick breakdown:

version	tests	run
20.19.0	✅	✅
21.19.0	skipped	skipped
22.14.0	❌	❌
23.19.0	❌	❌
24.19.0	❌	❌

As a result I'll have one commit per version