Fix type and type annotations issues in reproducible script

[BarbossHack]

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Description

"split" in diff.attribute_name.lower()

diff.attribute_name is str | None, we should avoid failure by checking if not None before

and not is_meta_attr

It is a duplicate (already checked in this condition), can be safely removed

return True

This function does not return bool, but list[XmlDifference]. If there is no difference, just return an empty list []

children1_by_tag: dict[str, list[Element]] = {}

Just add some type annotation where it couldn't be infered.