Output for OTLP (OpenTelemetry Protocol)

[nicolastakashi]

I believe would be very nice if bento supports output data to a OpenTelemetry Collector using OTLP (Could be HTTP or GRPC), that will unblock some nice integration.

[jem-davies]

Would it be possible to use the existing http_client output ? Or would it require a specific implementation for OpenTelemetery Collector?

Also note currently working on a gRPC component set: #546