By Martin Baccardax Upstart Tesla rival Rivan said supply chain challenges will limit its 2022 output to around 25,000 vehicles, around half of its prior forecast. Rivian Automotive (RIVN) – Get Rivian Automotive, Inc. Class A Report shares fell sharply Friday after the upstart EV maker warned that supply chain issues would halve its 2022 production forecasts following a wider-than-expected fourth quarter loss of $2.5 billion. Rivian, which is hoping to ramp-up production in the coming years to challenge established rivals such as Tesla (TSLA) – Get Tesla Inc Report in the global EV market, ha…