pos*: pos_loyalty, pos_restaurant, pos_sale, pos_adyen, pos_six, pos_stripe At the moment, the `pos` models don't have access to the `env` variable. This makes using `env` inside a model rather awkward. This PR makes it so all the pos models have access directly to `env`. closes odoo/odoo#124320 Task: 3358456 Related: odoo/enterprise#42209 Signed-off-by: Joseph Caburnay (jcb) <jcb@odoo.com>