Currently the support bundle reassignment task reads the set of "expunged nexus zones" from the blueprint and re-assigns them to an "alive" Nexus zone (whoever is running the reconfigurator).

it's critical that this step happens after the /PUT omicron-zones call completes -- otherwise, we could try to re-assign a support bundle from a nexus that is still running.

In the limit, as we work towards #7527 , we should rely on a mechanism for determining "zones we can cleanup" that is not "order of execution". In the meantime, however, we could make this current dependency more explicit.