By Jennifer Sieg Ambition A.M. meets Max Ottignon, founder of London-based branding agency Ragged Edge, to chat about what it takes to learn from your mistakes, and why it’s crucial to establish a growth mindset from the start. Entrepreneur Max Ottignon can still remember the embarrassment he felt the day his line manager told him things were no longer working out. He had just landed himself an internship at a prominent advertising agency in London, a role that he believed finally put him on track to achieving his dream job. Turns out, the now-proud co-founder and chief executive ofLondon-base…