Verify statsd sink

[prognant]

• Verify internal event processing metrics are tested via assert_X_compliance test helpers
• Update component_discarded_events_total to match the new instrumentation spec by adding reason to the emitted logs, and intentional to emitted logs and metrics
• Verify that the component correctly emits the correct error events per the component spec

[neuronull]

Have a couple changes on branch but there is an outstanding question I have about the sink framework and SinkSendError , where should we be reporting EventsDropped in the service based sinks, if not there?

The answer to that may imply more changes for this sink.