Fix formatting in header data
Fix formatting in header data

Summary: A few newlines were missing in the output for the header of `dex.py`.

Reviewed By: int3

Differential Revision: D16903926

fbshipit-source-id: e7b11bb61376a2d9838cf03342d4940376731c8c

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