add cancan for authorization

app/controllers/webhook_settings_controller.rb

@@ -1,15 +1,12 @@
 # frozen_string_literal: true
 
 class WebhookSettingsController < ApplicationController
-  def show
-    @encrypted_config =
-      current_account.encrypted_configs.find_or_initialize_by(key: EncryptedConfig::WEBHOOK_URL_KEY)
-  end
+  before_action :load_encrypted_config
+  authorize_resource :encrypted_config, parent: false
+
+  def show; end
 
   def create
-    @encrypted_config =
-      current_account.encrypted_configs.find_or_initialize_by(key: EncryptedConfig::WEBHOOK_URL_KEY)
-
     @encrypted_config.update!(encrypted_config_params)
 
     redirect_back(fallback_location: settings_webhooks_path, notice: 'Webhook URL has been saved.')
@@ -25,6 +22,11 @@ class WebhookSettingsController < ApplicationController
 
   private
 
+  def load_encrypted_config
+    @encrypted_config =
+      current_account.encrypted_configs.find_or_initialize_by(key: EncryptedConfig::WEBHOOK_URL_KEY)
+  end
+
   def encrypted_config_params
     params.require(:encrypted_config).permit(:value)
   end