Amazon.com Inc. has begun offering deliveries in as little as 10 minutes in New Delhi, revving up competition with local rivals in one of the fastest-growing segments of online retail.The online retail giant is expanding its “Now” service to the Indian capital, deepening a nascent foray into so-called quick commerce. It’s trying to keep up with rivals such as Eternal Ltd.’s Blinkit, Swiggy Ltd.’s Instamart and Zepto, which together pioneered the near-instant deliveries that’ve proven popular wit...