Some startups bristle at being called the Uber of something else. Asked to describe his company Rainforest QA, Fred Stevens-Smith volunteers it. If Uber seeks to maintain an advantage over rivals in part through the massive amount of data its collected on rides booked through its app, Stevens-Smith’s startup is doing the same with quality assurance tests. Founded in 2012, Rainforest spent much of 2017 focused on adding artificial intelligence to its thousands of QA…