c92a967 Fix incorrect call to koji API.

Authored and Committed by ralph 6 years ago
    Fix incorrect call to koji API.
    
    This was introduced months ago, but we never hit it.  I just saw it in
    the error logs.
    
    It looks like the call to `session.untaggedBuilds` expects a `name`
    argument, but `session.listTagged` does *not*.