was being overwritten at
This old code was taking precedent over the patched Action.php which includes the new function isFormkeyValidationOnCheckoutEnabled(); and some other stuff.
In my case two solutions where available.
Solution 1: After inspecting the old Action.php it was found that this file was not required and simply deleting this file allowed the new version of Action.php to take over.
Solution 2: Was to copy the function isFormkeyValidationOnCheckoutEnabled() and every other change made to Action.php over to the old Action.php to preserve any special behavior the template included in the first place.