[FIX] l10n_ma: Simplify VAT Report with Single Prorata Value

This update streamlines the Moroccan VAT report by requiring just one
prorata value, specifically the one determined and declared in form
ADC110.
Previously, the report erroneously necessitated a prorata value for each
line in the deductions breakdown, which was not in line with standard
requirements.
With this revision, the report aligns correctly by needing only
the single, correctly calculated prorata value as declared in
form ADC110.

Task-3517877

closes odoo#151492

Related: odoo/enterprise#51954
Signed-off-by: Florian Gilbert (flg) <[email protected]>

Author: moerradi