KRACOEUS_8502:fixes copy so that the prop person units are only saved on...

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So the issue we are having is because we 1.) save document with proposal person units for new proposal. 2.) replace proposal person units with a new list of units, but with same PKs 3.)next attempt at a find operation JPA flushes and throws the duplicate PK error.  

This PR removes the proposal person from the initial save then, readds them afterwards to avoid the duplicate insert.