* Check for url validity when creating TelemetryEndpoints
* Update code that used TelemetryEndpoints::new()
* Update commennts that referred to TelemetryEndpoints::new()
* Add tests for telemetry
* Fix typo and fix code in docs
* Return error on failing to override telemetry
* Use expect instead of suppressing errors on must-be-valid telemetry endpoints
* Update telemetry unit tests to use expect instead of unwrap
* Implement custom deserializer for TelemetryEndpoints
* Fix typo
* Apply suggestions from code review
Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>