Manage non existent processes in check status end-points

[josegar74]

Return the status of the components with a error to indicate that the process id provided doesn't exist, so the applications using the end-points can manage these cases.

Without the change the log file can be full of exceptions like this:

csw-harvester  | java.util.NoSuchElementException: No value present
csw-harvester  | 	at java.util.Optional.get(Optional.java:135)
csw-harvester  | 	at geocat.database.service.HarvestJobService.getById(HarvestJobService.java:81)
csw-harvester  | 	at geocat.service.GetStatusService.getStatus(GetStatusService.java:48)