[1.8.x] Fixed user_passes_test() signature in docs.

            return redirect('/login/?next=%s' % request.path)

        # ...

.. function:: user_passes_test(func, login_url=None, redirect_field_name='next')

.. function:: user_passes_test(test_func, login_url=None, redirect_field_name='next')

    As a shortcut, you can use the convenient ``user_passes_test`` decorator

    which performs a redirect when the callable returns ``False``::