Affirm’s IPO pop shows that the 2020 IPO fever hasn’t yet broken. The buy-now-pay-later fintech startup founded and run by PayPal co-founder Max Levchin went public on the Nasdaq yesterday, after having postponed its initial IPO plans in December to raise its share price from $33–$38 to $49. In doing so, Affirm was aiming to avoid a situation in…