Should we default to temurin?

[rossabaker]

http4s is now publishing with Temurin installed via Nix. Temurin is what sbt-typelevel uses by default. "jdk8" and "jdk17" are still Zulu in nixpkgs.

Basically, do we want to stick to Typelevel defaults or Nixpkgs defaults here where the twain meet?

[rossabaker]

I discovered this week that Temurin does not run on aarch64-darwin, at least for Java 8. The default devShell and the CI shells in http4s are now on disjoint JVMs. We could hack that with a branch on system, but, geez.