The type workaround provokes errors in `append`

[Acaccia]

The type workaround for the function append sets the same type for the argument as the type of the result. This leads to undefined behavior since we then use a memory.copy with the size of the result instead of the size of the argument.

Here is a failing example with the append function:

#[test]
fn double_append() {
    let snippet = "(append (append (list 1) 2) 3)";

    let expected = Value::Sequence(SequenceData::List(ListData {
        data: vec![
            Value::Int(1),
            Value::Int(2),
            Value::Int(3),
        ],
        type_signature: ListTypeData::new_list(TypeSignature::IntType, 3).unwrap(),
    }));

    crosscheck(snippet, Ok(Some(expected)))
}