SaleContext does not clear searched cards on finalizeSale

[jaikamat]

When a user clicks 'Finalize Sale' and then 'Yes', the searched-cards (on the left) are not cleared and their inventory values not updated, which may lead to edge cases when the same card is sold back-to-back. Users choose the incorrect quantity to sell, and thus are unable to fulfill an order in its entirety.

Clear the searched-cards by integrating them into the SaleContext emptying the array on sale submission.