bpo-36270: Doc: add link to traceback object reference (GH-13119)

(cherry picked from commit 9936371af298d465095ae70bc9c2943b4b16eac4)

Co-authored-by: Björn Meier <bjoern@opentrash.org>
diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst
index be1af37..5f8afa8 100644
--- a/Doc/library/sys.rst
+++ b/Doc/library/sys.rst
@@ -345,7 +345,7 @@
    ``(type, value, traceback)``.  Their meaning is: *type* gets the type of the
    exception being handled (a subclass of :exc:`BaseException`); *value* gets
    the exception instance (an instance of the exception type); *traceback* gets
-   a traceback object (see the Reference Manual) which encapsulates the call
+   a :ref:`traceback object <traceback-objects>` which encapsulates the call
    stack at the point where the exception originally occurred.