The Aasimar listings for alternate racial heritages list typical alignments. Do you need to match that alignment to take that alternate racial heritage, or is it just a suggestions? Is there a specific ruling on it for PFS?
You do not need to match the "typical alignment," and also there is no ruling on it. The heritages do not require a character to match that alignment, only suggest what a character of that heritage might be (based on the creature it derives from, like Angel or Garuda). Since the PFS Additional Resources page does not contradict this, you may choose any legal alignment.