chore: replace paste with pastey

[nabetti1720]

Issue # (if available)

Closed #101

Description of changes

This PR makes pastey a drop-in replacement for the long-unmaintained paste.

[tarcieri]

I'm not sure pastey is any better. Its CI is currently broken.

How much ident pasting is actually happening?

[nabetti1720]

I'm not sure pastey is any better. Its CI is currently broken.

How much ident pasting is actually happening?

I never thought it would be broken from the time of the release commit of pastey@v0.2.1. (And it seems like the CI keeps running once a day and breaking...)

It appears to be actively used to eliminate duplicate code in hash, hmac, aead/gcm, sign/ecdsa, verify/ecdsa, etc. There's no urgent reason to change this right now, so I'll close it.

[tarcieri]

I really wish this would get fixed upstream.

In the meantime I've also heard good stuff about with_builtin_macros which it looks like @stevefan1999-personal has used?

[stevefan1999-personal]

@tarcieri I used to use that before, until I decided to flatten it and use a simpler approach, that combine the benefits of both generic and macro based codegen approach, that I can have good debugging experience while ditching the need for paste by having the name fixated

[nabetti1720]

It was too early to close. We will leave it as Draft until pastey's CI is restored.
https://github.com/AS1100K/pastey/actions

I'll try to visit occasionally...