[FIX] l10n_it_edi_sdicoop: previous fix didn't adapt tests

Previous fix for self invoice RegimeFiscale = RF18
didn't take into consideration the test that was specifically
targeting it, so now it's broken in v14.
The other versions are safe as the staging does run the l10n tests.

closes odoo/odoo#104942

See: https://github.com/odoo/odoo/pull/104780


Signed-off-by: Josse Colpaert <jco@odoo.com>

addons/l10n_it_edi_sdicoop/tests/expected_xmls/reverse_charge_bill.xml

@@ -20,7 +20,7 @@
                 <Anagrafica>
                     <Denominazione>Alessi</Denominazione>
                 </Anagrafica>
-                <RegimeFiscale>RF01</RegimeFiscale>
+                <RegimeFiscale>RF18</RegimeFiscale>
             </DatiAnagrafici>
             <Sede>
                 <Indirizzo>Avenue Test rue </Indirizzo>