gh-99767: mark PyTypeObject.tp_watched as internal use only in table (#100271)

Author: carljm

Doc/c-api/typeobj.rst

@@ -147,7 +147,7 @@ Quick Reference
    +------------------------------------------------+-----------------------------------+-------------------+---+---+---+---+
    | :c:member:`~PyTypeObject.tp_vectorcall`        | :c:type:`vectorcallfunc`          |                   |   |   |   |   |
    +------------------------------------------------+-----------------------------------+-------------------+---+---+---+---+
-   | :c:member:`~PyTypeObject.tp_watched`           | char                              |                   |   |   |   |   |
+   | [:c:member:`~PyTypeObject.tp_watched`]         | char                              |                   |   |   |   |   |
    +------------------------------------------------+-----------------------------------+-------------------+---+---+---+---+
 
 .. [#slots]