It just says "Davis" and "23." I believe that it could be any Davis, or a name chosen at random to show what #23 would look like on the Celtics.. The last name Davis is the 7th most common in North America, not to mention the 45th most common in England and 68th most common in Wales.
Clearly, the chances that they are referring to "Anthony Davis" the basketball player are obviously very, very slim.
Mike