Add option for "infinite loop" for Testimonial Carousel widgets

It would be great to have an “infinite loop” option for testimonial carousel widgets, where once you scroll to the last testimonial it just keeps going by starting at the beginning again.

Right now - when you scroll past the final testimonial, the entire carousel visually rewinds. By allowing you to “scroll past” the last testimonial to start over again, it gives the feeling of a larger number of testimonials (vs. a visual rewind, which is a stark reminder you’ve reached the end).