Make status code explicit

app/controllers/webhooks_controller.rb

@@ -6,7 +6,7 @@ class WebhooksController < ApplicationController
   def lndhub
     begin
       payload = JSON.parse(request.body.read, symbolize_names: true)
-      return unless payload[:type] == "incoming"
+      head :no_content and return unless payload[:type] == "incoming"
     rescue
       head :unprocessable_entity and return
     end