Use websockets to connect to blueapi #96

As of DiamondLightSource/blueapi#1413, we can connect to blueapi using a web socket. In the queue worker, we should use this feature and have a websocket for each task, for the duration of the task. This means we can stop polling blueapi to check when a task is finished.

Acceptance Criteria

• Websockets are used to connect to blueapi in the queue worker.