[FIX] note: convert unicode to utf-8 so it can gracefully handle by etherpad

- Task: https://www.odoo.com/web?#id=8946&view_type=form&model=project.task&action=333&active_id=131
- Pad: https://pad.odoo.com/p/r.6w3Hg0iEEkK64ypp