The shares have been on a roll, and today's news is keeping it going.The stock of Rivian Automotive (RIVN 9.66%) is jumping again on Monday. Shares of the electric vehicle (EV) maker popped as much as 12% in early trading today to start the week. That jump kept the momentum going for Rivian shares.The stock has soared by more than 30% since mid-April. That move came after the company introduced its next-generation lineup of midsize electric SUVs in March and after a large funding grant from the State of Ill ...