JDK 17 and Scala 3.8.x

[Mike Beckerle]

JDK 17+ will be required for Scala 3.8 and up.

https://www.scala-lang.org/news/next-scala-lts-jdk.html

This may have implications for our port to scala 3. I'm not sure our
Cyberian users can move up to JDK 17.