Found it:

https://pixels.com/featured/animals-my-vote-cat-funny-political-jacob-zelazny.html?product=adult-tshirt

Also on amazon: https://www.amazon.com/voting-shirt-person-political-t-shirt/dp/B07MJWHQH4

Another non-Amazon: https://www.redbubble.com/i/t-shirt/I-Vote-For-Cats-by-LemonRindDesign/29732932.NL9AC