Elon Musk on Tuesday laughed at how Tesla Inc.’s (NASDAQ:TSLA) stock rallied after Jim Cramer said in June that he would buy legacy automaker General Motors‘ stock over the EV giant’s. What Happened: CNBC “Mad Money” host and former hedge fund managerJim Cramersaid in late June that he would rather buy General Motors shares than Tesla’s. GM CEO Mary Barra is “crushing it,” Cramer then said. However, Tesla’s shares have surged significantly since then, thanks to the company’s second-quarter delivery numbers published last week. Although lower than the corresponding quarter last year, Tesla’s se…