Scottie Pippen’s new memoir, “Unguarded,” is a master class in settling scores, or creating new ones. Beginning in the prologue, Pippen expresses anger at Michael Jordan over “The Last Dance,” the 2020 ESPN documentary on the 1990s Chicago Bulls, which Pippen writes “glorified Michael Jordan while not giving nearly enough praise to me and my proud teammates.” Pippen gets more caustic from there.