You can use the following code: <li>{{join(split(1.Text; newline); "</li><li>")}}</li>. This code will split your text into array elements and then join them again with the HTML tags as a separator. Finally, you need to add the first and last tags around the function to get the HTML list items.
I have attached a blueprint (4.0 KB) for your reference so you can check what I did in more detail.