RuntimeWarning: coroutine 'RedisBackend._pubsub_listener' was never awaited

[laxuscullen]

I had to clone the broadcaster folder of this repo since the public version via pip does not work with redis auth.

This only shows when using gunicorn and not with uvicorn. This crashes the api right away. The code is same as #123

[laxuscullen]

@alex-oleshkevich this is another issue I am facing.