Consider reducing the test compile 'classpath' in WhiteboxTestCompileArgumentProvider

[jjohannes]

Right now we add the --module-path but do not remove the modules from the classpath. This seems to work but it is not 100% clear what happens in situation where the classpath is used as well (i.e. users add --add-reads ...=ALL-UNNAMED).
I think we could also reduce the classpath to only include the non-modules.

[jjohannes]

There is no hook for this in Gradle. If you manually add a -classpath argument in the WhiteboxTestCompileArgumentProvider there will just be two -classpath arguments passed to the compiler.

Closing this as:

• It does not matter in a clean setup where you have no -classpath at all
• In the --add-reads ...=ALL-UNNAMED setup (which you should avoid anyway) it still does not seem to be a problem in practice

[jjohannes]

Fixed by 0c918e8