[FIX] helpdesk_mgmt: company_id should come from team

Otherwise, creating tickets from fetchmail would always set odoobot's company in new tickets, potentially in contrast to team's company

helpdesk_mgmt/models/helpdesk_ticket.py

@@ -67,10 +67,7 @@ def _read_group_stage_ids(self, stages, domain, order):
     unattended = fields.Boolean(related="stage_id.unattended", store=True)
     tag_ids = fields.Many2many(comodel_name="helpdesk.ticket.tag", string="Tags")
     company_id = fields.Many2one(
-        comodel_name="res.company",
-        string="Company",
-        required=True,
-        default=lambda self: self.env.company,
+        related="team_id.company_id", string="Company", store=True, readonly=True
     )
     channel_id = fields.Many2one(
         comodel_name="helpdesk.ticket.channel",