Fix a memory leak in ObjectHandling.c

Cython/Utility/ObjectHandling.c

@@ -1445,8 +1445,12 @@ static CYTHON_INLINE PyObject* __Pyx_PyObject_CallOneArg(PyObject *func, PyObjec
 }
 #else
 static CYTHON_INLINE PyObject* __Pyx_PyObject_CallOneArg(PyObject *func, PyObject *arg) {
-    PyObject* args = PyTuple_Pack(1, arg);
-    return (likely(args)) ? __Pyx_PyObject_Call(func, args, NULL) : NULL;
+    PyObject *result;
+    PyObject *args = PyTuple_Pack(1, arg);
+    if (unlikely(!args)) return NULL;
+    result = __Pyx_PyObject_Call(func, args, NULL);
+    Py_DECREF(args);
+    return result;
 }
 #endif