[DOC]: GIL with 3.13

[ShalokShalom]

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What version (or hash if on master) of pybind11 are you using?

not relevant

Problem description

Python 3.13 offers to unlock the GIL.

That is not reflected in the documentation yet.

https://github.com/pybind/pybind11/blob/stable/docs/advanced/misc.rst#global-interpreter-lock-gil

Reproducible example code

Is this a regression? Put the last known working version here if it is.

Not a regression

[ShalokShalom]

(As a note: I suggest calling it

"Seamless operability between C++11+ and Python"

in the Github topic description and the top of the documentation.

For a moment, I thought it's not compatible for more modern versions of C++ with the current wording.)