[FIX] base: merging unreadable pdfs

To Reproduce
============
- create two Vendor Bills and attach to each one a PDF from the ones
provided by the client on the ticket.
- select these two bills and and try to print Original Bills an error will be raised

Problem
=======
while merging these PDFs, PyPDF2 throws a `TypeError` which is not caught by the server

Solution
========
catch `TypeError` to raise a UserError

opw-3285540

closes odoo/odoo#121313

X-original-commit: 5053620c640136025f5b37c5b8d233ad63825389
Signed-off-by: abla001 <abla@odoo.com>

odoo/addons/base/models/ir_actions_report.py

@@ -626,7 +626,7 @@ class IrActionsReport(models.Model):
             try:
                 reader = PdfFileReader(stream)
                 writer.appendPagesFromReader(reader)
-            except PdfReadError:
+            except (PdfReadError, TypeError):
                 raise UserError(_("Odoo is unable to merge the generated PDFs."))
         result_stream = io.BytesIO()
         streams.append(result_stream)