[FIX] hr_fleet : UserError on empty pdf

Step to reproduce:
- Print a 'claim car report' on a car with no attachment

Current Behaviour:
- Print a empty PDF

Behaviour after PR:
- The landing page explain to the user there is no pdf to print

opw-2714493

closes odoo/odoo#81687

Signed-off-by: Damhaut Florian (flda) <flda@odoo.com>

addons/hr_fleet/controllers/main.py

@@ -67,6 +67,9 @@ class HrFleet(Controller):
                 page.mergePage(header_pdf.getPage(0))
                 writer.addPage(page)
 
+        if not writer.getNumPages():
+            request.not_found(_('There is no pdf attached to generate a claim report.'))
+
         _buffer = io.BytesIO()
         writer.write(_buffer)
         merged_pdf = _buffer.getvalue()

addons/hr_fleet/i18n/hr_fleet.pot

@@ -118,6 +118,11 @@ msgid ""
 "go on vehicle page. Do you want to proceed?"
 msgstr ""
 
+#. module: hr_fleet
+#: code:addons/hr_fleet/controllers/main.py:0
+msgid "There is no pdf attached to generate a claim report."
+msgstr ""
+
 #. module: hr_fleet
 #: model:ir.model,name:hr_fleet.model_res_users
 msgid "Users"