The stock is slowly mounting a comeback.The boom and bust cycle in electric vehicles (EVs) may be coming full circle. Stocks like Rivian Automotive (RIVN 0.85%) plummeted over the last few years as the bubble popped in the sector. Many companies have gone bankrupt, unable to make their business models viable.Rivian remains unprofitable today, but it has large backers and a plan to greatly expand its manufacturing footprint through the rest of this decade. At around $15 a share today, Rivian stock has bounce ...