Very soon, residents of this hilly city will become the first Americans to test out Uber’s self-driving car service. It is a historic moment not just for the ride-hailing company, but also for robotic cars in general. For many people, the technology will finally become a reality, one they can touch and experience rather than just read about. Uber has been conducting its driverless-car tests on open roads since May. People in Pittsburgh say they have…