use webhook urls instead of encrypted configs

app/views/shared/_settings_nav.html.erb

@@ -56,7 +56,7 @@
             <%= link_to 'API', settings_api_index_path, class: 'text-base hover:bg-base-300' %>
           </li>
         <% end %>
-        <% if can?(:read, EncryptedConfig.new(key: EncryptedConfig::WEBHOOK_URL_KEY, account: current_account)) %>
+        <% if can?(:read, WebhookUrl) %>
           <li>
             <%= link_to 'Webhooks', settings_webhooks_path, class: 'text-base hover:bg-base-300' %>
           </li>