[Orchestrator] - Endpoint error message when the expected result is not received. (Case of orchestrator url wrongly set).

[Orchestrator] - Endpoint error message when the expected result is not received. (Case of orchestrator URL wrongly set).

When we use the client, it reads the configuration file of orchestrator.conf. If the endpoints are wrongly set, we must have an error message specifying a potential unavailability of the service or wrong URL / endpoints reached.