Added an azure functions adapter

[leopf]

Closes #3451

🎯 Changes

I have added the azure functions adapter and an example. It is missing tests and documentation.

✅ Checklist

• I have followed the steps listed in the Contributing guide.
• If necessary, I have added documentation related to the changes made.
• I have added or updated the tests related to the changes made.

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Name	Status	Preview	Comments	Updated
www	❌ Failed (Inspect)			Dec 22, 2022 at 3:19AM (UTC)

[KATT]

Honestly, I'd love to have this in the repo and I think you made really good work here.

However, the reality though is that we can't maintain more adapters at the moment (unless @microsoft starts sponsoring us 😅) ; we already have loads of them, the surface area of tRPC is quite large, and no one works on tRPC full-time.

This would make a great third party library to be put on https://trpc.io/awesome