Map ErrorKind::IsADirectory and ErrorKind::NotADirectory when targetting Rust 1.83

[Tpt]

Rust 1.83 stabilized io::ErrorKind::IsADirectory and io::ErrorKind::NotADirectory. It would be nice to update the functions converting between PyErr and io::Error to map them to IsADirectoryError and NotADirectoryError.

[davidhewitt]

👍 this seems very reasonable, to ship in 0.24.

[Tpt]

Maybe later, sadly I am not aware of a way to conditionally compile code based on the rustc version so adding this means PyO3 targets Rust 1.83+

[Icxolu]

We have cfg infrastructure for things like this in place in pyo3-build-config. I added this in #4747.

[Tpt]

Amazing! Thanks!