CSV Output Fix: Improve how "Add another group" inputs appear in outputs

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The form designer can select a Tangy Group (tangy-input-groups) input and then create a set of inputs. Outputs of these values are awkward in the CSVs.

We need a better strategy to output these values.

One strategy that needs to be further defined in the output them in a separate csv file. To consider with this strategy:

1. Linking of the main csv file to the sub-files and vice versa.
2. when to output the csvs -- always or on selection by the user?

[esurface]

@lachko Can you add context to this?

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context added in planning meeting