It’s a really tiny easter egg, but you can find it while doing the “Haum Sweet Haum” mission. You’ll be doing a lot of hacking in this quest, so you will come across HAUM systems computers. If you hack into one of them and check for installed software, you will see the icon for Tom Clancy’s The Division.
It was an obvious choice for developers to include this reference in Watch Dogs 2, as they did the same with The Division. That game is just as full of Ubisoft-related easter eggs as this one.