SSDM-13457: Some safe coding to avoid search crashing on a rare scenario that...

SSDM-13457: Some safe coding to avoid search crashing on a rare scenario that shoudn't happen but happens

server-application-server/source/java/ch/systemsx/cisd/openbis/generic/server/dataaccess/db/HibernateSearchDAOV3Adaptor.java

@@ -167,8 +167,8 @@ public class HibernateSearchDAOV3Adaptor implements IHibernateSearchDAO {
             {
                 registrator.setFirstName("Missing");
                 registrator.setLastName("Missing");
-                registrator.setUserId("Missing");
-                registrator.setEmail("Missing");
+                registrator.setUserId("system");
+                registrator.setEmail("");
                 registrator.setActive(false);
             } else {
                 registrator.setFirstName(registratorPersonPE.getFirstName());