Inner Radiance Torrent is common, but it is Limited:
A limited option can be selected only if specifically allowed by a boon — whether from the Achievement Points system, a Chronicle Sheet, or another other option from a Pathfinder Society source — even if the option is common or if the character meets the normal prerequisites or access requirements printed in the option’s source.
Which boon gives access to it?
As a Limited option, you must have a Boon that specifically says you gain access to it. Going through the List of Boons available (link to your account on Paizo.com), there is no mention of inner radiance torrent, "Limited" (looking for something along the lines of "Select a limited spell from a curated list..."), nor any general access to Secrets of Magic elements*.
*This isn't quite true because Esoteric Spellcaster - Secrets of Magic exists. However, it only provides access to Uncommon spells, specifically nudge the odds, spiritual attunement or zero gravity.
