enable free threading for python

[hendrikmuhs]

best to my knowledge we can enable free threading.

[hendrikmuhs]

due to msgpack-python, free threading is not enabled:

  <frozen importlib._bootstrap>:491
    <frozen importlib._bootstrap>:491: RuntimeWarning: The global interpreter lock (GIL) has been enabled to load module 'msgpack._cmsgpack', which has not declared that it can run safely without the GIL. To override this behavior and keep the GIL disabled (at your own risk), run with PYTHON_GIL=0 or -Xgil=0.

Fix is already on master, next release will enable it.