In the module website, the relational field website_id is defined twice,
once for ir_ui_view and a second time for res_config_settings, for the
former we perform an ondelete='cascade', which means that when the
website model is unlinked, the field is unlinked as well.
This is not done for the website_id field in res_config_settings, which
instead defaults to setting the field to NULL, which violates a not-null
constraint and therefore causes issues when trying to modify/save
settings.
To solve this, a hard delete of the ir_model_field website_id is
performed during the uninstall process of the website module.
Fixes#21905
OPW 803018
Adrian Torres
9f583717e5