revert unpack-only behavior temporarily
revert unpack-only behavior temporarily

Summary: Stop putting voltron metadata into dexen dir during unpack for now, causing stats bot issues.

Differential Revision: D4654354

fbshipit-source-id: a615c0a4313713766d58866b9d9dc21c54a79628

facebook/redex,facebook/redex,facebook/redex,facebook/redex,facebook/redex,facebook/redex,facebook/redex,facebook/redex,facebook/redex