Check that the values in `Tools/wasm/config.site-wasm32-wasi` are still necessary

[brettcannon]

https://github.com/python/cpython/blob/main/Tools/wasm/config.site-wasm32-wasi was created a while ago, so it would probably be good to see if they still apply under e.g. WASI 0.2 and WASI SDK 20 or newer.