Fix incorrect PyObject_CallFunction usage (remove extra NULL argument)

This PR fixes incorrect calls to PyObject_CallFunction where an
extra NULL argument was passed despite the format string already
specifying the complete argument list.
PyObject_CallFunction does not use a NULL terminator; it relies
solely on the format string to determine how many arguments to read.
Providing more arguments than required results in undefined behavior
due to va_list misalignment.

The affected calls:
- PyImport_Import() — "OOOOi" was given 6 arguments instead of 5
- deque_copy() — "Oi" was given 3 arguments instead of 2

Both have been corrected by removing the superfluous NULL.
No functional changes beyond fixing the API misuse.

Signed-off-by: Yongtao Huang <yongtaoh2022@gmail.com>

Author: hyongtao-code

Modules/_collectionsmodule.c

@@ -634,7 +634,7 @@ deque_copy_impl(dequeobject *deque)
                                      (PyObject *)deque);
     else
         result = PyObject_CallFunction((PyObject *)(Py_TYPE(deque)), "Oi",
-                                       deque, old_deque->maxlen, NULL);
+                                       deque, old_deque->maxlen);
     if (result != NULL && !PyObject_TypeCheck(result, state->deque_type)) {
         PyErr_Format(PyExc_TypeError,
                      "%.200s() must return a deque, not %.200s",

Python/import.c

@@ -4067,7 +4067,7 @@ PyImport_Import(PyObject *module_name)
        Always use absolute import here.
        Calling for side-effect of import. */
     r = PyObject_CallFunction(import, "OOOOi", module_name, globals,
-                              globals, from_list, 0, NULL);
+                              globals, from_list, 0);
     if (r == NULL)
         goto err;
     Py_DECREF(r);