Congrats on almost finishing Sitecore XC 9.2 installation. Only few installation steps before it is finished, but this error keeps pooping up.
Json file Common.RebuildIndexes.json that is located in SIF->Configuration->Commerce->Comon, has a few RequestTimeout properties that define how long will install script wait before trying to start step again. Importunately if you have slow PC or Virtual Machine, default values are not giving your PC enough time to finish rebuilding indexes. By increasing these values, your PC will have time to complete this steps and installation will finish successfully.