test: Fix flaky HostSuite.TestAddFailingJob
test: Fix flaky HostSuite.TestAddFailingJob

We don't guarantee the order that events are delivered in.

Signed-off-by: Jonathan Rudenberg <3692bfa45759a67d83aedf0045f6cb635a966abf@titanous.com>

philiplb/flynn,philiplb/flynn,lmars/flynn,lmars/flynn,lmars/flynn,flynn/flynn,philiplb/flynn,flynn/flynn,lmars/flynn,lmars/flynn,philiplb/flynn,flynn/flynn,flynn/flynn,flynn/flynn,philiplb/flynn