Are we creating a problem by giving a temp a pass on our dress code?

Q: “We have an employee hired through a temporary agency who wore a shirt to work that said “Caliente.” I know this means hot. I think it’s inappropriate for her to wear this shirt in a business setting and if she were an employee, I would probably tell her that. However, since she’s a temp, but likely to become a permanent employee, what should I do? - Lee, Texas