Fix sql request

[stonebuzz]

Checklist before requesting a review

Please delete options that are not relevant.

• I have performed a self-review of my code.
• I have added tests (when available) that prove my fix is effective or that my feature works.
• I have updated the CHANGELOG with a short functional description of the fix or new feature.
• This change requires a documentation update.

Description

• It fixes No more calculations #549

Fix bad SQL request

SQL Error "1054": Unknown column 'price_ati` - `price_discounted' in 'SELECT' in query "SELECT SUM(`price_ati`) AS `priceTTC`, SUM(`price_discounted`) AS `priceHT`, SUM(`price_ati`` - ``price_discounted`) AS `priceTVA` FROM `glpi_plugin_order_orders_items` WHERE `plugin_order_orders_id` = '3716'"

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[stonebuzz]

Need : #551