Well, as far as licorice, ginger, cinnamin, and peppermint go, they are all safe for pregnancy. In fact licorice, peppermint, and ginger are all wonderful for helping ease queeziness in the first trimester!
Practically all nutritional supplements, herbs & herbal teas, etc carry so-called "warnings". It is just a stupid procedure brought about by the FDA... basically no company that is not a "conventional" drug or medicine company can claim cures through their products, and since they can claim no cures they are not responsible for any harm that the products may produce. It's just a blanket warning, drink the tea without worry!