Fix a client error raised when deleting a collection
Fix a client error raised when deleting a collection

This was introduced by a bad copy/paste in 681547c932.

RafaelPalomar/girder,Kitware/girder,data-exp-lab/girder,RafaelPalomar/girder,manthey/girder,RafaelPalomar/girder,data-exp-lab/girder,jbeezley/girder,data-exp-lab/girder,kotfic/girder,Kitware/girder,manthey/girder,data-exp-lab/girder,manthey/girder,girder/girder,Kitware/girder,jbeezley/girder,data-exp-lab/girder,manthey/girder,kotfic/girder,kotfic/girder,jbeezley/girder,girder/girder,girder/girder,RafaelPalomar/girder,kotfic/girder,girder/girder,RafaelPalomar/girder,kotfic/girder,jbeezley/girder,Kitware/girder