MOD assign context company_id in partner creation

Related to this card: https://trello.com/c/PkBCQRg0/198-en-crear-un-nou-partner-aquest-es-crea-sense-assignaci%C3%B3-de-company-i-per-tant-queda-a-la-vista-de-totes-les-ce

On create new partners, the field company_ids must get the context company_id as default value. If not any new partner remains visible across all the companies.

energy_communities/models/res_partner.py

@@ -9,6 +9,15 @@ class ResPartner(models.Model):
 
     gender = fields.Selection(selection_add=[("not_binary", "Not binary"),
                                              ("not_share", "I prefer to not share it")])
+    @api.model
+    def create(self, vals):
+        current_company = self.env.company
+        if self.env.user not in (self.env.ref("base.user_root"), self.env.ref("base.user_admin")):
+            if vals.get('company_ids', False):
+                vals['company_ids'][0][-1].append(current_company.id)
+
+        new_partner = super(ResPartner, self).create(vals)
+        return new_partner
 
     def cron_update_company_ids_from_user(self):
         partner_with_users = self.search([('user_ids', '!=', False), ('user_ids.id', '!=', SUPERUSER_ID)])