[IMP] base: rename country group "Europe" to "European Union"

Given the group only contains EU27 members and the UK was specifically removed in 52cdfd22d7 it seems clear this group represents the European Union speifically rather than any other interpretation of "Europe".

Rename the group to match.

closes odoo/odoo#101051

Signed-off-by: Xavier Morel (xmo) <xmo@odoo.com>

odoo/addons/base/data/res_country_data.xml

@@ -1591,7 +1591,7 @@
         </record>
 
         <record id="europe" model="res.country.group">
-            <field name="name">Europe</field>
+            <field name="name">European Union</field>
             <field name="country_ids" eval="[Command.set([
                 ref('at'),ref('be'),ref('bg'),ref('hr'),ref('cy'),
                 ref('cz'),ref('dk'),ref('ee'),ref('fi'),ref('fr'),