[3.14] gh-132657: optimize PySet_Contains for frozenset (GH-141183) (gh-141773)

(cherry picked from commit 7211a34)

Co-authored-by: Kumar Aditya <[email protected]>

Author: miss-islington

Objects/setobject.c

@@ -2746,7 +2746,9 @@ PySet_Contains(PyObject *anyset, PyObject *key)
         PyErr_BadInternalCall();
         return -1;
     }
-
+    if (PyFrozenSet_CheckExact(anyset)) {
+        return set_contains_key((PySetObject *)anyset, key);
+    }
     int rv;
     Py_BEGIN_CRITICAL_SECTION(anyset);
     rv = set_contains_key((PySetObject *)anyset, key);