Renamed a test model field added in [16345] so it doesn't keep the test DB...

Renamed a test model field added in [16345] so it doesn't keep the test DB ceation process from finishing under Oracle.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16499 bcc190cf-cafb-0310-a4f2-bffc1f526a37