prepare the environment before executing the command in wrapper

[Nidrop]

My host (Void linux) package for JDK by default sets the environment variable JAVA_HOME (path to JDK), which is not compatible with Archlinux. So every time I have to unset or change the JAVA_HOME environment variable before starting the IDE from junest. Otherwise the IDE will not be able to correctly detect its own JDK, which was installed in junest. It would be nice to run the preparation script or smth before executing the wrapping command.