Test errors on java 17

[adamw]

Something related to interceptors & Unsafe

[adamw]

For now this is "fixed" by adding --add-opens java.base/java.lang=ALL-UNNAMED to JAVA_OPTS for java9+ builds. I think a proper fix would involve adding a module-info.java which would expose the test package as a module (see https://stackoverflow.com/a/41265267/362531), but I don't think that's possible due to sbt/sbt#3368.

@SethTisue maybe this will be interesting for you as well :)

[SethTisue]

trying it: scala/community-build#1462