Procurement schedulers now catch all exceptions and log them

This PR is to improve the procurement schedulers: instead of just catching the SQL Operational Errors (and retrying them later in one case), they catch all exceptions (so that the scheduled task is not stopped), log them as warnings, and still retrying the one case for OperationalError.

It was also done for upstream in https://github.com/odoo/odoo/pull/3841 .