add `jdk9Test` to default execution #429
add `jdk9Test` to default execution #429

It seems that some time between introduction and now (possibly with some Gradle upgrade?) `jdk9Test` started to not be executed by default anymore when `test` is executed. Also for some reason the `jdk9Test` classpath at the moment does not contain the `testCompile` dependencies anymore.

Signed-off-by: Peter Gafert <cdbfcea01cf62f959f8b10da948a53f2869d9b6c@tngtech.com>
TNG/ArchUnit,TNG/ArchUnit