[IMP] base: always show overwrite box

It is not a technical feature

odoo/addons/base/wizard/base_language_install_views.xml

@@ -10,7 +10,7 @@
                     <field name="state" invisible="1"/>
                     <group states="init">
                         <field name="lang"/>
-                        <field name="overwrite" groups="base.group_no_one"/>
+                        <field name="overwrite"/>
                     </group>
                     <group states="done" colspan="4">
                         <label string="The selected language has been successfully installed.