Generalize the last remnants of "sha" and "sha1" in this file and rename
it to reflect that we're not just able to handle SHA-1 these days.
We need to update one test to check for an updated error string.
Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>