Settings: fix signature of a post_syncdb signal handler
Settings: fix signature of a post_syncdb signal handler

This handler is used to create the classification dummy project. Due to
the sender and the app arguments to the handler being the same and the
other arguments not in use, there was effectively no problem for the
handler. Nevertheless, the signature requires this extra argument to be
correct.

fzadow/CATMAID,fzadow/CATMAID,fzadow/CATMAID,fzadow/CATMAID