gh-118915: Add document of PY_MONITORING_IS_INSTRUMENTED_EVENT

Author: Yuki Kobayashi

Doc/c-api/monitoring.rst

@@ -190,3 +190,9 @@ would typically correspond to a python function.
 .. c:function:: int PyMonitoring_ExitScope(void)
 
    Exit the last scope that was entered with :c:func:`!PyMonitoring_EnterScope`.
+
+
+.. c:function:: int PY_MONITORING_IS_INSTRUMENTED_EVENT(uint8_t ev)
+
+   Return true if the event corresponding to event ID *ev* is
+   a :ref:`local event <monitoring-event-local>`.

Doc/library/sys.monitoring.rst

@@ -165,6 +165,8 @@ events, use the expression ``PY_RETURN | PY_START``.
 
 Events are divided into three groups:
 
+.. _monitoring-event-local:
+
 Local events
 ''''''''''''