Refactor all ActivityPub deliveries to be serialized and signed through one concern (#10966)

app/services/reblog_service.rb

@@ -3,6 +3,7 @@
 class ReblogService < BaseService
   include Authorization
   include StreamEntryRenderer
+  include Payloadable
 
   # Reblog a status and notify its remote author
   # @param [Account] account Account to reblog from
@@ -53,10 +54,6 @@ class ReblogService < BaseService
   end
 
   def build_json(reblog)
-    Oj.dump(ActivityPub::LinkedDataSignature.new(ActiveModelSerializers::SerializableResource.new(
-      reblog,
-      serializer: ActivityPub::ActivitySerializer,
-      adapter: ActivityPub::Adapter
-    ).as_json).sign!(reblog.account))
+    Oj.dump(serialize_payload(reblog, ActivityPub::ActivitySerializer, signer: reblog.account))
   end
 end