Add a default price component option to RulesDataUICommercePrice::inputForm()

Now that #1558380: Add a price comparison condition has landed, let's improve it to work better with the Set a data value action. Right now if you use that action on a price field you can set the amount and currency code, but the price field's data array will remain empty. This means if you do this during sell price calculation, you don't get the necessary price component in the data array that makes order total calculation work properly.

What I'd like to see is a new option in the form to choose the default price component type to use upon save, and in the validate callback we can initialize the price component array to have a component of that type. Providing the component will fix this: