“Dora and the Lost City of Gold” is not a satire, however, nor is it an attempt to crossbreed Nickelodeon’s popular bilingual character, who made her first TV appearance in 2000, with “Mean Girls.” Even as it strikes a gently irreverent tone, the film also embodies its heroine’s positive energy: We understand that the world would be a better place if the rest of us were more like Dora, not the other way around.