You dismiss the action in the handler which gets called when the action is tapped. The documentation describes the handler as follows
The block to execute when the user taps the button associated with this action. UIKit makes a copy of the block you provide. When the user selects the action represented by this object, UIKit executes your handler block on the app’s main thread.
Independently, I suppose you could just set the table views editing property to false.
tableView.setEditing(false, animated: true)