Jack Dorsey, co-founder and chief executive officer of Twitter Inc. and Square Inc., listens during the Bitcoin 2021 conference in Miami, Florida, on Friday, June 4, 2021.Eva Marie Uzcategui | Bloomberg | Getty ImagesBlock shares jumped more than 10% in extended trading on Friday, as the fintech company gets set to join the S&P 500, replacing Hess.It's the second change to the benchmark this week, after S&P Global announced on Monday that ad-tech firm The Trade Desk would be added to the S&P 500...