[FIX] purchase: Do not display notes/sections in purchase reporting

The issue is when we create a new PO with notes/sections and these notes/sections are showed on purchase reporting and only the products were supposed to appear there.

This issue happens because the SQL query wasn't applying any filter to the lines. The solution is apply a filter by display_type.

Steps to reproduce:
1) Go to Purchase App -> Purchase Orders -> Create a new PO with notes/sections
2) Go to Reporting -> View as pivot
3) You'll be able to see the section/notes you just created

closes odoo/odoo#118823

Opw: 3245933
X-original-commit: 8eab549c
Signed-off-by: Adrien Widart <awt@odoo.com>
Signed-off-by: malv-odoo <malv@odoo.com>