[FIX] hr_timesheet: uninstall project's 'timesheet' config

Steps :
Go to project > settings.
Check 'timesheet' config and save.
Uncheck it back and save.

Issue :
See errors in the logs, due to on delete restrict.

Cause :
Record 'hr_timesheet.internal_project_default_stage' from data
is deleted when hr_timesheet is uninstalled.
Yet some project task records still use it, so we can't delete it.

Fix :
Delete the corresponding ir.model.data to keep the stage,
but unlink it from the 'hr_timesheet.internal_project_default_stage' ref.

task-2998416

closes odoo/odoo#101633

Related: odoo/enterprise#32022
Signed-off-by: Laurent Stukkens (ltu) <ltu@odoo.com>

addons/hr_timesheet/__init__.py

@@ -48,3 +48,5 @@ def _uninstall_hook(cr, registry):
     project_ids = env['res.company'].search([('internal_project_id', '!=', False)]).mapped('internal_project_id')
     if project_ids:
         project_ids.write({'active': False})
+
+    env['ir.model.data'].search([('name', 'ilike', 'internal_project_default_stage')]).unlink()