[Detector] Detector for EventHub connectivity issues

parent item: #1866

- Analysis of errors surfaced.
- Ramp up on detector code base.
- Event Hub connectivity issues - surface and summarize errors/exceptions from Functions logs indicating connection issues to the Event Hub service (these would be logged by the Event Hub SDK which manages the connection and calls the WebJobs extension when there is an event(s) to process)

- Network access blocked - Should surface as errors logged by an underlying SDK - might require intentionally staging an environment with firewall restricted network access added in the middle of successful processing to induce the errors.