Currently, eStargz compression doesn't preserve the original tar metadata
(header bytes and their order). This causes failure of `TestGetRemote` because
an uncompressed blob converted from a gzip blob provides different digset
against the one converted from eStargz blob even if their original tar (computed
by differ) are the same.
This commit solves this issue by fixing eStargz to preserve original tar's
metadata that is modified by eStargz.
Signed-off-by: Kohei Tokunaga <ktokunaga.mail@gmail.com>
Kohei Tokunaga