There's actually a transform called "flatten" (it might be called "convert array to rows" in some versions of Wrangler) that you can use to turn lists into rows. The catch is that you need to have your list typed as an array first. Here's the documentation on flatten: https://docs.trifacta.com/display/PE/Flatten+Transform
If you need to turn your list into a valid array, you should first use the transform called "extractlist" (also called "convert list to array"). Here's the documentation on extractlist: https://docs.trifacta.com/display/PE/Extractlist+Transform
Hope that helps!
