Notify when a Service Bus entity size goes above or below a defined size threshold

[SeanFeldman]

Usecase scenario

Scaling out/in MUs based on entity size thresholds I'd define.
For example, issue an event when it's above 80% of the size and issue an event when it's below 50%.
This would allow me to create a subscriber for SB Event Grid events to perform the scaling in a fully automated fashion base on entity status.

[SeanFeldman]

@axisc fyi