Publish for Scala 3 (aka Dotty)

[phdoerfler]

I imagine this is easier said than done but, well, now there's an issue for it.
Thanks!

[javierarrieta]

Referencing a question in the global circe Scala 3 plans:

circe/circe#1754 (comment)

[felixbr]

I took a look at the code and it's full of macros, shapeless 2, and other things which are not supported by Scala 3 at all.

My intention was to write a Scala 3 version from scratch with the same apis but no Scala 2 compatibility otherwise. In the meantime @Lasering started to add configuration options to the Scala 3 version of circe-generic, so that will probably solve the problem for me.

Not sure which features will still be missing if the PR mentioned above is included in 0.15.0.