Increases to Contract where Service already exists to not duplicate

Currently this is what SalesBuildr does if you have an existing service on there of qty 6 and add another of qty 1:

It adds another line of the same item to the Contract with a count of 1x.

This has a direct flow on effect at invoicing where the client receives two lines of the same item (6 and 1) rather than a summed quantity of 7.

Instead of adding the additional service line, it should have detected that 6x already existed and increased by 1x as at today (pro-rata or not determined by Autotask settings.)