WebDeposit: `db.func.max` call fix
WebDeposit: `db.func.max` call fix

Reviewed-by: Jiri Kuncar <2bdffcb416fed3002465740d19a053a39918cbe5@cern.ch>

inveniosoftware/invenio-deposit,inveniosoftware/invenio-deposit,inveniosoftware/invenio-deposit,inveniosoftware/invenio-deposit