Remove database app_name and app_uuid (#7562)

- Remove database app_name, app_uuid
  - This is handled automatically by the database class
- Remove redundant database::new()

app/extensions/app_defaults.php

@@ -53,8 +53,6 @@
 					$p = permissions::new();
 					$p->add('extension_edit', 'temp');
 
-					$database->app_name = 'extensions';
-					$database->app_uuid = 'e68d9689-2769-e013-28fa-6214bf47fca3';
 					$database->save($array, false);
 					unset($array);