If there was any doubt as to Olivia Rodrigo ‘s pop-rock bonafides, she got the co-sign tonight from Blondie ‘s lead vocalist Debbie Harry, who popped up in a surprise cameo on Saturday Night Live to introduce the singer. Rodrigo, in her first time pulling double duty, performed on the Studio 8H stage for the third time, debuting her new song “drop dead.” The three-time Grammy-winning singer-songwriter released the track and accompanying music video — dreamily directed by Petra Collins at the Louvre — two weeks ago . The actress-cum-musician transitioned seamlessly from host to musical guest, donning an airy green and pink dress and rocking out to the boisterous and energetic track. Her upcoming album, you seem pretty sad for a girl so in love,  will drop June 12. Watch on Deadline The “Heart of Glass” singer is the latest prominent musical figure to pop by for a quick introduction.…