In order to use two different versions of skiko in one app (using
multiple classloaders), it is required to use the unpacking strategy, as
the skiko.library.path is a system property, which is same for all
classloaders.

This change will allow to use presigned natives shipped together with
the app, while still being able to use multiple versions as the property
skiko.library.path will be loaded from current classloader resources,
with fallback to system property.
Co-authored-by: Jakub Senohrabek <jakub@senohrabek.net>