jsoniter-scala support

[borissmidt]

I see that you have support for a lot of Json libraries.
Tapir seems to have support for json-iter but sttp does not implement it yet.
It seems it is rather easy to implement a new json implementation so i wouldn't mind giving it a try.

[adamw]

Sure, go ahead :)

[plokhotnyuk]

Currently jsoniter-scala supports JVM and Scala.JS for 2.11, 2.12, 2.13, and 3 versions of Scala, so it should be easy to integrate it with sttp.

Please prefer parsing and serialization of UTF-8 encoded payload from/to Array[Byte], not String for better efficiency.

[Pask423]

Implemented in #1248