Add support for OpenTelemetry

[mosabua]

after dependencies like dropwizard are updated.

Needs architectural discussion how to best add this feature. Probably should talk to @electrum who added this to Trino.

@vishalya is interested on working on this feature.

[mosabua]

@martint mentioned that this will be easier if we migrate to Airlift instead of using Dropwizard

Also fyi @willmostly

[lambrospetrou]

This would be amazing to have. I have been looking to see if the gateway publishes metrics somehow that we could get them from outside, without implementing a custom listener module similar to ClusterStateListenerModule with our own ClusterStatsObserver.

Ideally, we would like to get those cluster stats metrics (and anything else from the gateway) without having to add any code in the gateway itself (or having code that depends on the gateway jar due to weird repo issues on our side), so that we can use the published gateway as-is, and then own the monitoring infra from the outside.

[mosabua]

This depends on our move to airlift - see #41