Service is considered running if there is no pod

[olevitt]

The logic for determining if a service is running seems to be flawed when there is no pod at all (e.g when the pod are not created due to requests exceeding quotas).
If there is no pod at all then the service should probably be considered as not running (not sure what state it should be considered to be but that's probably tied to work on #749 )

[fcomte]

we also need to fix the onyxia-api logic to find all the pods