Event Hubs should allow reuse of an existing storage resource

### Is there an existing issue for this?

- [x] I have searched the existing issues

### Is your feature request related to a problem? Please describe the problem.


When I add Event Hubs to my deployment and run the local emulator, I end up getting a storage container, even though I've already got one configured.

### Describe the solution you'd like

It would be nice to be able to tell the Event Hubs local deployment to simply reuse my existing storage account for whatever it needs, and perhaps even with a prefix or an effective namespace/container of some kind?

### Additional context

_No response_