[FIX] l10n_*: don't write on country_id in demo

Writing the country_id of the main company in demo data disables demo
data installation if installing multiple l10n, this is caused by a wrong
check of the vat field (base_vat).

Two approaches can be used here:

- Always write on country_id in all l10n demo data
NB: this also implies writing the country_id first in order for the
vat check to be done using the right country code
- Never write on country_id in any l10n demo data

The prefered approach for the moment is to never write on the country_id
of the main company.
This approach is easier to apply as it is a mimimal diff and the first
approach would require deeper changes to the code in order to allow
writing all the information in a single `record` tag in the demo data

closes odoo/odoo#34905

Signed-off-by: Christophe Monniez (moc) <moc@odoo.com>

addons/l10n_in/data/res_partner_demo.xml

@@ -2,7 +2,6 @@
 <odoo noupdate="1">
 	<!-- Update main company -->
     <record id="base.main_company" model="res.company">
-        <field name="country_id" ref="base.in"/>
         <field name="state_id" ref="base.state_in_gj"/>
         <field name="vat">24BBBFF5679L8ZR</field>
     </record>

addons/l10n_it_edi/data/account_invoice_demo.xml

@@ -3,7 +3,6 @@
     <data noupdate="1">
         <!-- add VAT, codice fiscal and tax system for main company -->
         <record id="base.main_company" model="res.company">
-            <field name="country_id" ref="base.it"/>
             <field name="vat">IT00410128888</field>
             <field name="l10n_it_codice_fiscale">0123456789987654</field>
             <field name="l10n_it_tax_system">RF01</field>