jobsub_fetchlog --list return success if sandboxes found on any server
jobsub_fetchlog --list exits non zero if it cannot find any sandboxes with the specified constraints.
However, when there are multiple servers, it may find sandboxes on one server and not on the others.
Currently, it loops through all of the servers logically ANDing the results, so if one server has no sandboxes the return code is non-zero.
The correct behavior should be a logical OR of the servers results, if it finds sandboxes on any server it should return success, i.e. exit with 0 status