Mikaela Shiffrin might be a professional skier now, but if she’d opened a LinkedIn account as a 9-year-old, her profile would have said something different. “I wanted to be a rainbow horse,” the six-time overall World Cup champion admitted when asked what she originally wanted to be when she grew up. Shiffrin hung out with about 40 young girls as part of “The GOAT Gives Back” event on Saturday at Copper Mountain. The invite-only private ski day …