ci: run unit tests in CI
Run unit tests in both Cirrus and GitHub CI. For sharded CI instances
(currently just Windows on GitHub), run only on the first shard. This is
OK while we have only a single unit test executable, but we may wish to
distribute tests more evenly when we add new unit tests in the future.
We may also want to add more status output in our unit test framework,
so that we can do similar post-processing as in
ci/lib.sh:handle_failed_tests().
Signed-off-by: Josh Steadmon <steadmon@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>