branch tests: add to --sort tests
Further stress the --sort callback in ref-filter.c. The implementation
uses certain short-circuiting logic, let's make sure it behaves the
same way on e.g. name & version sort. Improves a test added in
aedcb7dc75e (branch.c: use 'ref-filter' APIs, 2015-09-23).
I don't think all of this output makes sense, but let's test for the
behavior as-is, we can fix bugs in it in a later commit.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>