What’s New In Python 3.12: bad highlighting for Py_NewInterpreterFromConfig() example

In the "[PEP 684: A Per-Interpreter GIL](https://docs.python.org/3/whatsnew/3.12.html#pep-684-a-per-interpreter-gil)" section of "What’s New In Python 3.12", the C code snippet is highlighted as if it was Python.


### Linked PRs
* gh-113609
* gh-113610