Macro append_to_inittab

macro_rules! append_to_inittab {
    ($module:ident) => { ... };
}

Available on crate feature macros and neither PyPy nor GraalPy only.

Add the module to the initialization table in order to make embedded Python code to use it. Module name is the argument.

Use it before prepare_freethreaded_python and leave feature auto-initialize off