Fixed #26290 -- Documented that a QuerySet for pagination should be ordered.

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``object_list``

    A list, tuple, Django ``QuerySet``, or other sliceable object with a

    ``count()`` or ``__len__()`` method.

    A list, tuple, ``QuerySet``, or other sliceable object with a ``count()``

    or ``__len__()`` method. For consistent pagination, ``QuerySet``\s should

    be ordered, e.g. with an :meth:`~django.db.models.query.QuerySet.order_by`

    clause or with a default :attr:`~django.db.models.Options.ordering` on the

    model.

``per_page``

    The maximum number of items to include on a page, not including orphans