Shares of the salad chain soared on a strong earnings report. Shares of Sweetgreen (SG 0.58%), the fast-casual salad chain, were surging again last month after the company posted another strong earnings report and talked up its expanding robotic kitchen program, known as Infinite Kitchen. According to data from S&P Global Market Intelligence, the stock finished last month up 37%. As you can see from the chart, all the stock's gains came on the earnings report in the middle of the month. In fact, the stock a ...