This handles the case where a job when from no-deployment to deployment
with canaries.
Consider a case where a `max_parallel=0` job is submitted as version 0,
then an update is submitted with `max_parallel=1, canary=1` as verion 1.
In this case, we will have 1 canary alloc, and all remaining allocs will
be version 0. Until the deployment is promoted, we ought to replace the
canaries with version 0 job (which isn't associated with a deployment).
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