Updates go-winio to the latest version. The main important fix here is
to go-winio's backuptar package. This is needed to fix a bug in sparse
file handling in container layers, which was exposed by a recent change
in Windows.
go-winio v0.5.1: https://github.com/microsoft/go-winio/releases/tag/v0.5.1
Signed-off-by: Kevin Parsons <kevpar@microsoft.com>