Taylor Swift onstage at the Eras Tour.Shirlaine Forrest/TAS24/Getty Images for TAS Rights ManagementTaylor Swift's newest single, "I Knew It, I Knew You," debuted at No. 1 on the Billboard Hot 100.Swift now has the third-most No. 1 hits of any artist, trailing Mariah Carey and The Beatles.Swift's biggest hits also include "Blank Space," "Anti-Hero," and "The Fate of Ophelia."Since releasing her first No. 1 album in 2008, Taylor Swift has enjoyed…