fixup tests
fixup tests

now that some of the tests upload more than 1 artifact, we can use the
len of the chan to keep track of how many were successfully uploaded.

Signed-off-by: Bohan Chen <c9a015a7f6482b47c219aa2cbd78ba6c88c0a327@pivotal.io>

concourse/concourse,concourse/concourse,concourse/concourse,concourse/concourse,concourse/concourse