Hooks has been deprecated in favor of subscribing to order_recalculate

Please see PR #[3553](solidusio/solidus#3553) for more information concerning this change.

app/decorators/models/solidus_klarna_payments/spree/order_decorator.rb

@@ -5,13 +5,6 @@ module Spree
     module OrderDecorator
       KLARNA_SESSION_LIFETIME = 48.hours
 
-      def self.prepended(base)
-        base.class_eval do
-          register_update_hook(:update_klarna_shipments)
-          register_update_hook(:update_klarna_customer)
-        end
-      end
-
       def update_klarna_session(session_id: nil, client_token: nil)
         update!(
           klarna_session_id: session_id,

app/subscribers/solidus_klarna_payments/klarna_subscriber.rb

@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+module SolidusKlarnaPayments
+  module KlarnaSubscriber
+    include ::Spree::Event::Subscriber
+
+    event_action :update_klarna_shipments, event_name: :order_recalulated
+    event_action :update_klarna_customer, event_name: :order_recalulated
+
+    def update_klarna_shipments
+      order = event.payload[:order]
+      order.update_klarna_shipments
+    end
+
+    def update_klarna_customer
+      order = event.payload[:order]
+      order.update_klarna_customer
+    end
+  end
+end