Add tests to confirm that path collisions are properly detected by
checkout workers, both to avoid race conditions and to report colliding
entries on clone.
Co-authored-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
