[FIX] mail, change _get_access_link to get the action id

[ismaelcj]

Description of the issue/feature this PR addresses:
When sending an email, for example an invitation to follow a sale order, the address of the related document is wrong. Specifically, the action is the xml_id instead of an integer id. So the link is not working.

Current behavior before PR:
An example of wrong url: http://127.0.0.1:8069/web?db=odoo_test#action=mail.action_mail_redirect&login=admin%40odoo.com&res_id=35611&model=sale.order

Desired behavior after PR is merged:
The expected url: http://127.0.0.1:8069/web?db=odoo_test#action=103&login=admin%40odoo.com&res_id=35611&model=sale.order

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[pedrobaeza]

Please make the corresponding PR upstream

[ismaelcj]

Done odoo#16595

[ismaelcj]

I've tested it now on runbot and it works well, so there must be something wrong in my server.

Sorry for the inconvenience.