Commit 894d4a23fba made BuildFile use TarSum, which doesn't support
compressed tar archives.
This breaks builds from git url, which compressed it with bzip2.
Instead, just pass it uncompressed.
Docker-DCO-1.0-Signed-off-by: Paul Lietar <paul@lietar.net> (github: plietar)
Upstream-commit: 562a23576328c1586f1be968fa15cb075267138c
Component: engine