Consider declaring queues as "auto-delete" for transient sinks

[phijor]

If a Sink dies between subscribing and starting to consume metrics, its data queue will not get deleted and starts collecting metric data that is never consumed.

Consider adding an auto-delete to the queue (or something similar) so that this does not happen. At least for Sinks that are short lived are not expected to reuse their data queue after a reconnect.

[bmario]

The queues are already declared as auto-delete, but that doesn't help.

Auto-delete (queue that has had at least one consumer is deleted when last consumer unsubscribed)

What we need is a queue-TTL.

[phijor]

We decided to have the manager use a queue TTL by default when declaring Sink data queues.

This is being implemented in metricq/metricq-manager#38.

[phijor]

Closed via #38.