On one of the sweatiest nights of the summer, the heat did not stop an intimate crowd from jumping along to the angsty bops of Olivia Rodrigo’s new album and joining her in the shared pain of romantic love. “You’re rocking out, I fucking love you!” Rodrigo yelled from the small stage. The pop star announced the surprise concert Thursday morning, offering $25 tickets only to fans who arrived to Warsaw, a small Greenpoint, Brooklyn venue, in person starting at 10 A.M. The show comes after the June release of Rodrigo’s third studio album,You Seem Pretty Sad for a Girl So in Love, and marked the opportunity for Rodrigo to play some of her…