Welcome to the community, my friend! That's an excellent question.
There is not a way to program the action button for Siri. However, you can use the multifunction button to access Siri. The multifunction button is the middle button on the right earcup (play/pause button). If you press and hold that for 2 seconds it will act as an extension of your phone and allow you to communicate with Siri.
I hope that this information helps! Let me know if you need any more information.