This update removes a duplicate function from the Point of Sale module. The `pushExternalOrderToBlackbox` function was essentially a copy of another existing function, streamlining the codebase and improving efficiency. This change ensures consistent functionality and reduces potential for errors.

Remove useless function `pushExternalOrderToBlackbox` that was doing the same as `pushOrderToBlackbox(order, true)`.

This function was introduced in the following PR: https://github.com/odoo/enterprise/pull/102280

Forward-Port-Of: odoo/enterprise#102425