[3.13] Doc: remove duplicate GitHub issue reference in "What's New in Python 3.13" (GH-143654) (#143657)

Doc: remove duplicate GitHub issue reference in "What's New in Python 3.13" (GH-143654)
(cherry picked from commit aa8578d)

Co-authored-by: emmanuel <[email protected]>

Author: miss-islington

Doc/whatsnew/3.13.rst

@@ -2346,7 +2346,7 @@ Limited C API Changes
   * :c:func:`PySys_AuditTuple`
   * :c:func:`PyType_GetModuleByDef`
 
-  (Contributed by Victor Stinner in :gh:`85283`, :gh:`85283`, and :gh:`116936`.)
+  (Contributed by Victor Stinner in :gh:`85283` and :gh:`116936`.)
 
 * Python built with :option:`--with-trace-refs` (tracing references)
   now supports the :ref:`Limited API <limited-c-api>`.