Steps to reproduce:
- set demo to receive notifs in Odoo
- go to employees
- click "launch plan" for demo user
- login as demo user
- Click on the link for the activity that is sent in discuss

Issue:
There is no chatter in the view

Explanation:
the view of en employee coming from messaging is always
hr.employee.public that does not contain the chatter.

opw-2990577

closes odoo/odoo#100959

Signed-off-by: Kevin Baptiste <kba@odoo.com>