Before this commit, when you create a lead from livechat with the command /lead, the public user is used inside the lead.
Because the public user is archived, and self.env.ref('base.public_partner').user_ids return an empty recordset.
closes odoo/odoo#71792
X-original-commit: 04ff97e40e3869b1350dca325251747629443e69
Signed-off-by: Thibault Delavallee (tde) <tde@openerp.com>