[style] Use 'x | y' syntax for processors as well (#43189)
* Use 'x | y' syntax for type annotations
* reapply style etc
* fix type using themselves....
* fix
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Co-authored-by: Cyril Vallez <cyril.vallez@huggingface.co>
Co-authored-by: Cyril Vallez <cyril.vallez@gmail.com>
