Update http.cookiejar.rst

Author: LamentXU123

Doc/library/http.cookiejar.rst

@@ -258,7 +258,7 @@ contained :class:`Cookie` objects.
    You probably don't need to call this method because expired cookies are never
    sent back to the server (provided you're using :class:`DefaultCookiePolicy`).
    This method is called by :class:`CookieJar` itself every so often. It *could*
-   only be useful when you are customizing a `CookiePolicy` with your own
+   only be useful when you are customizing a :class:`CookiePolicy` with your own
    expiring logic.
 
    Note that the :meth:`save` method won't save expired cookies anyway (unless you ask