In the Phacility cluster, if the members of an instance billing account all become disabled, the PhortuneSubscriptionWorker task fails and retries indefinitely.

This most commonly happens when:

• a user launches a paid instance;
• that user is later disabled because they're a "security researcher", commercial message enthusiast, etc.

The simple fix here is to make "billing account has no active members" a permanent failure. I think this is reasonable for now.

Down the line, this might lead to some weird cases where a user could intentionally goad staff into disabling all the members of a billing account in order to disable billing activity for an instance. If the billing cycle triggers, billing-related state changes (like suspension) will also never trigger, so you get an instance for free forever provided you don't ever need to interact with support. But I think we can cross that bridge when we come to it.