account_operating_unit: inter ou balance lines are displayed in the invoice

[gurneyalex]

Module

account_operating_unit

Describe the bug

When I use the inter operating balance feature, the module adds lines to account move which are displayed as invoice lines. They get printed out in the PDF report.

To Reproduce

Affected versions: 15.0 at least

Steps to reproduce the behavior:

1. set up inter operating unit balance on the company, and a balance account
2. configure the sales journal to have no operating unit
3. create a customer invoice with no operating unit, and 2 products on two different lines
4. go to the "journal items" tab, set the first product line on OU B2B, for instance, the second product line on OU B2C and the account receivable and tax lines ou the main OU
5. save and post the invoicee

Expected behavior the balance lines are not displayed as an invoice lines, they are only visible in the journal items tab. They are also not printed in the PDF report.

Current status:

Additional context

It would be also super cool to have this working with an OU on the account move, and only generate the balancing lines for the lines which don't match that OU.