Gluten-free gnocchi are available in some larger supermarkets.  Swap regular gnocchi for the gluten-free variety and use cornstarch in place of the flour to thicken the soup.  When using cornstarch as a thickener, do not add it dry to the soup pot like you would the flour.  Reserve about one cup of the cold chicken stock or broth and whisk the cornstarch into it to form a slurry.  Pour the slurry into the rest of the broth once it has been added to the vegetables.