_PyUnicode_AsString is deprecated in python3.14

[e-kwsm]

python/src/converter/builtin_converters.cpp

Line 56 in 32da86d

return PyUnicode_Check(obj) ? const_cast<void*>(reinterpret_cast<const void*>(_PyUnicode_AsString(obj))) : 0;

https://docs.python.org/3.14/deprecations/index.html#id2

_PyUnicode_AsString(): use PyUnicode_AsUTF8().