Fixed #11450 -- Corrected markup problem in contenttype docs. Thanks to seveas for the report.

    .. method:: models.ContentTypeManager.clear_cache()

        Clears an internal cache used by

        :class:`~django.contrib.contenttypes.models.ContentType>` to keep track

        :class:`~django.contrib.contenttypes.models.ContentType` to keep track

        of which models for which it has created

        :class:`django.contrib.contenttypes.models.ContentType>` instances. You

        :class:`django.contrib.contenttypes.models.ContentType` instances. You

        probably won't ever need to call this method yourself; Django will call

        it automatically when it's needed.