By Medha Singh (Reuters) – Bitcoin loves flirting with the mainstream. But now, as the U.S. president says he wants to get serious, it may be getting cold crypto feet. When Joe Biden ordered officials to prepare reports on the role of cryptocurrencies in future finance last Wednesday, bitcoin leapt as much as 9% and ether 8%, as many crypto fans hailed a potential milestone in mainstream acceptance. “The real importance of it is that the president of the United States is talking about crypto,” said Jack McDonald, CEO of Standard Custody, a firm handling digital asset custody solutions for inst…