stop an asset being managed by housekeeper if it has no contributor
stop an asset being managed by housekeeper if it has no contributor

some assets have no contributor due to coming form JERM harvesting. The logic treated these as abandoned, however they can have managers and creators. Changed the logic to make them manageable if they have no managers.

stuzart/seek,HITS-SDBV/seek,HITS-SDBV/seek,stuzart/seek,stuzart/seek,HITS-SDBV/seek,HITS-SDBV/seek