Hi Grzegorz!
Thank you for posting your issue here!
There is no way of changing this user home location for the Google directory. The Google App Engine Launcher would re-create it each time it is launched, in exactly the same location, together with a new google_appengine_launcher.ini file in it.
You may consider moving the directory and creating symbolic links to allow proper functioning of the Launcher, if moving this directory is a must.
What is the main reason for wanting to get rid of this directory? Let me know if I may help further.