[IMP] base: prevent changing contact type of users

When a user is linked to a contact, the type should not be
modified. Otherwise, the res.partner type may become incompatible with
the res.user record (e.g. is set as a private address and a user no
longer has access to its own user)

Fixes odoo/odoo#48177

closes odoo/odoo#48590

Signed-off-by: Martin Trigaux (mat) <mat@odoo.com>

odoo/addons/base/views/res_partner_views.xml

@@ -168,7 +168,7 @@
 
                     <group>
                         <group>
-                            <field name="type" groups="base.group_no_one"/>
+                            <field name="type" groups="base.group_no_one" attrs="{'readonly': [('user_ids', '!=', [])]}"/>
                             <span class="o_form_label o_td_label" name="address_name">
                                 <b attrs="{'invisible': [('type', '!=', 'contact')]}">Company Address</b>
                                 <b attrs="{'invisible': [('type', '!=', 'invoice')]}">Invoice Address</b>