Revert "[molecules] drop sabayon-steambox from GNOME and KDE due to licensing issues"

This reverts commit 8b8f817491beb63acaa37f12dfe494f71086ed21.
Revert "[remaster] drop steambox install boot mode"

This reverts commit 2cfcfdb1aaa88747555ec721cd74d58e96b4f041.