Two ironworkers who sustained serious injuries at a job site when a large steel rack system collapsed onto them has settled their lawsuit for nearly $20 million.Defendants Amazon.com LLC, Duke Realty Services and Steel King Industries Inc. agreed to the $19.9 million deal on Aug. 23 after five days of trial before U.S. District Judge Ruben Castillo.Amazon hired general contractor Duke Realty Services, based in Indianapolis …