fix: database error handling during import of a non-user item The code to handle the case of retired and active users causing errors during import can get called on other db errors as well (e.g. out of memory in postgresql). The code that trys to detect/repair the out of order user case hard coded the db.user class. This crashed when a db error occurred when loading another data object (e.g. msg). Fix the crash by using the proper db object class for the object class being loaded. Credit to Norbert Schlemmer for finding this.