slurm scheduler: need to report if the job is done

[BerengerBerthoul]

Currently, if the slurm job is done but the worker processes have not send their report (e.g. because they crashed), the master process still waits for the messages till the end of time

We should make the job send a message that it is done (after the wait). If the master process receives this message, it should print the job that did not come back