Fixed #14923 -- corrected a typo in the logging documentation. Thanks to...

Fixed #14923 -- corrected a typo in the logging documentation.  Thanks to David Foerster for the report.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@14991 bcc190cf-cafb-0310-a4f2-bffc1f526a37