post https://sandbox.dev.clover.com/v3/merchants//orders//line_items//modifications
Creates a modification, a record of a modifier as it exists at the time it is applied to the lineItem. To view current modifications, use the 'expand=modifications' query parameter on the lineItem. To learn more about applying a modification, see: https://docs.clover.com/build/working-with-orders/#add-item-modifiers.