tax report does not show base amount when a tax consist of group of taxes

[crispyduck00]

Module

account_financial_report

Describe the bug

tax report does not show base amount when a tax consist of group of taxes

To Reproduce

16

Steps to reproduce the behavior:

1. configure a tax that has tax computation = group of taxes
2. ad a tax that has also a grid for base configured
3. assign group tax to a invoice
4. check tax report, it does not show the base amount

Expected behavior
report should show also the base amount if tax is part of a group of taxes

Additional context
Tried now some hours to reproduce why it behaves like tis, but was not able to figure out why the base amount is not show.

Side note why I would like to use group of taxes:
For a for me also unclear reason, but here I guess it is because the sum is 0, when using standard accounting for some EU countries (tested with AT, BE, DE), the tax for e.g. RC where at the same time -100% as well as +100% are assigned to different grids and accounts, the report based on grid shows always the tax as 0 (but here the base is shown).
So the Idea was to split it up into two and group it, which works and shows the correct tax amount, but now the base is 0.