Side-step sed line-ending "corruption" leading to t6038 failure.

Side-step sed line-ending "corruption" leading to t6038 failure.

By default, MSYS sed throws away CR from CRLF line-endings.  Tests
t6038.5 and t6038.6 employ sed to normalize conflict output of git-merge
for validation purposes.  These tests expect CRLF line-endings to be
present in the normalized output of git-merge, and thus fail when sed
undesirably removes CR.  Fix by employing sed's -b/--binary switch to
suppress its default behavior of dropping CR characters.

Acked-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Pat Thoyts <patthoyts@users.sourceforge.net>