Spaces in paths not supported in javalib on Windows

[jchyb]

Example:

import java.nio.file.Paths
object Main {
  def main(args: Array[String]): Unit = {
    val path = Paths.get("test file")
  }
}

Native bahavior:

java.nio.file.InvalidPathException: java.nio.file.InvalidPathException: Illegal character ` ` in path at index 4: test file
        at java.lang.StackTrace$.currentStackTrace(Unknown Source)
        at java.lang.Throwable.fillInStackTrace(Unknown Source)   
        at scala.collection.immutable.WrappedString$$$Lambda$1.apply(Unknown Source)
        at scala.scalanative.nio.fs.windows.WindowsPathParser$.apply(Unknown Source)
        at Main$.main(Unknown Source)
        at <none>.main(Unknown Source)
        at <none>.__scrt_common_main_seh:(d:\a01\_work\2\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288)(Unknown Source)
        at <none>.BaseThreadInitThunk(Unknown Source)
        at <none>.RtlUserThreadStart(Unknown Source)

Expected (jvm) behavior:
Runs fine, we can of course also do any actual operations on that file.