Refactor 'body=' patch in rest controller to hooks.py

CHANGELOG:

### REFACTOR
- [#460](https://gitlab.com/coopdevs/odoo-somconnexio/-/merge_requests/460) Refactor 'body=' patch in rest controller to hooks.py

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After install it merge https://gitlab.com/coopdevs/odoo-somconnexio-inventory/-/merge_requests/57