stop synchweb hammering the api when cas authentication fails
stop synchweb hammering the api when cas authentication fails

tcspain/SynchWeb,tcspain/SynchWeb,tcspain/SynchWeb,DiamondLightSource/SynchWeb,DiamondLightSource/SynchWeb,tcspain/SynchWeb,tcspain/SynchWeb,DiamondLightSource/SynchWeb,DiamondLightSource/SynchWeb,DiamondLightSource/SynchWeb,DiamondLightSource/SynchWeb,tcspain/SynchWeb