builder/virtualbox: check the proper file path
builder/virtualbox: check the proper file path

suma/packer,msabramo/packer,Kaixiang/packer,suma/packer,TranscendComputing/packer,msabramo/packer,zyegfryed/packer,Kaixiang/packer,smerrill/packer,smerrill/packer,smerrill/packer,TranscendComputing/packer,TranscendComputing/packer,smerrill/packer,msabramo/packer,TranscendComputing/packer,patricklucas/packer,suma/packer,patricklucas/packer,zyegfryed/packer,Kaixiang/packer,msabramo/packer,suma/packer,Kaixiang/packer,patricklucas/packer,patricklucas/packer,zyegfryed/packer,zyegfryed/packer