l10n_it_delivery_note: fix delivery note invoice assignment by using invoice IDs

[francesco-ooops]

Describe the bug

Fix Mixing apples and oranges.

File "/opt/odoo/custom/oca/l10n-italy/l10n_it_delivery_note/wizard/delivery_note_create.py", line 132, in confirm
sale_order_id._assign_delivery_notes_invoices(sale_order_id.invoice_ids)
File "/opt/odoo/custom/oca/l10n-italy/l10n_it_delivery_note/models/sale_order.py", line 92, in _assign_delivery_notes_invoices
ready_invoice_ids = [
File "/opt/odoo/custom/oca/l10n-italy/l10n_it_delivery_note/models/sale_order.py", line 95, in
if invoice_id in invoice_ids
File "/usr/lib/python3/dist-packages/odoo/models.py", line 5601, in contains
raise TypeError("Mixing apples and oranges: %s in %s" % (item, self))
Exception

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
File "/usr/lib/python3/dist-packages/odoo/http.py", line 652, in _handle_exception
return super(JsonRequest, self)._handle_exception(exception)
File "/usr/lib/python3/dist-packages/odoo/http.py", line 317, in _handle_exception
raise exception.with_traceback(None) from new_cause
TypeError: Mixing apples and oranges: 899717 in account.move(899717,)

To Reproduce

Affected versions:

• 14.0 [FIX] l10n_it_delivery_note: fix delivery note invoice assignment by using invoice IDs #4591
• 16.0 [16.0][FIX] l10n_it_delivery_note: fix delivery note invoice assignment by using invoice IDs #4593

Expected behavior
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Additional context
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