Potential race condition between Studio API and RabbitMQ event loop.

[andreidenissov-cog]

It looks like we may have race condition when we create StudioML-level RMQ instance
and begin using it while its internal event handling thread is still starting.
On establishing RMQ connection, the whole queue setup logic is handled by sequence of async callbacks, which are not guaranteed to finish yet when first StudioML API calls are executed.