[FIX] auth_ldap: encode python ldap's output as utf8

Non-ascii characters in LDAP don't cause a python unicode string in
returned ldap entries, this commit fixes this.

Before this commit, further string operations on ldap values with
non-ascii characters fail.

closes odoo/odoo#40761

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

addons/auth_ldap/models/res_company_ldap.py

@@ -167,7 +167,7 @@ class CompanyLDAP(models.Model):
         """
 
         return {
-            'name': ldap_entry[1]['cn'][0],
+            'name': tools.ustr(ldap_entry[1]['cn'][0]),
             'login': login,
             'company_id': conf['company'][0]
         }