Refactor Azure Service Bus: move create_subscription to hook

[perry2of5]

This commit refactors the logic to create a subscription into the hook. The operators should not be accessing the connection to Azure Service Bus directly. This code belongs in the hook to promote reuse.

In addition, it allows the caller to pass a RuleFilter to apply to the subscription to limit which messages are sent to the subscription.

@dabla: this addresses part of your comments on PR 44675