Fix fatal error when parsing URLs in Node adapter

[Conduitry]

Fixes the bug with the Node adapter in #801, and also performs the tidying I mentioned in that issue for the Vercel adapter.

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[benmccann]

Thanks for the quick fix and sorry for breaking! I forgot the tests don't cover adapter-node

[samccone]

I have sent a PR to add test coverage for adapter-node which would have caught this case
#807