[FIX] tools: try decrypting PDF with empty password

Steps:
- Install accounting
- On the dashboard, try to upload an "encrypted" PDF like this one https://launchpadlibrarian.net/24827090/DS-0157.pdf

Bug:
Traceback:
PyPDF2.utils.PdfReadError: file has not been decrypted

Explanation:
In 13.0, these errors were caught in a catch all `except` as shown here: https://github.com/odoo/odoo/blob/4e089041252c25cc197a30f9e285d82f7162d809/addons/account_facturx/models/account_move.py#L303-L328

From this SO comment: https://stackoverflow.com/questions/52047944/pdfbox-extracting-blanks-from-pdf-encrypted-with-no-password#comment91054285_52047944



> A PDF can be encrypted with two passwords: a user password and an owner password. When a PDF is encrypted with a user password, you can't open the document in a PDF viewer without entering that password. When a PDF is encrypted with an owner password only, everyone can open a PDF without that password, but some restrictions may be in place.

From time to time, we get a PDF encrypted with an owner password. The
content is still readable, but PyPDF2 fails because it thinks the PDF is
encrypted. With this fix, we try to unwrap the PDF by providing an empty
user password. This way, PyPDF2 thinks the content is now decrypted.

However, PyPDF2 only supports decrypting versions 1 and 2 of the
encryption implementation. If the version is different, we skip reading
the attachments and carry on to allow the user to upload the document.

opw:2375993

closes odoo/odoo#62557

Signed-off-by: backspac <backspac@users.noreply.github.com>