Allow for Replace Values in Append to Grid component

In the setup of a Grid Variable, users only have the option to append or prepend values. This means that whatever is contained as a default value in the Grid Variable remains in the Grid Variable, even after the prepend/append operation. This default value can then break the process that the grid variable is iterating over.

The most logical solution would be to add a Replace option in the Operation field. Allowing for Replace will remove the default value and replace it with the values intended by the user.