Warning: require_once(/app/wp-admin/includes/plugin.php): Failed to open stream: No such file or directory in /app/wp-settings.php on line 571

Fatal error: Uncaught Error: Failed opening required '/app/wp-admin/includes/plugin.php' (include_path='.:/usr/local/lib/php') in /app/wp-settings.php:571 Stack trace: #0 /app/wp-config.php(113): require_once() #1 /app/wp-load.php(50): require_once('/app/wp-config....') #2 /app/wp-blog-header.php(13): require_once('/app/wp-load.ph...') #3 /app/index.php(17): require('/app/wp-blog-he...') #4 {main} thrown in /app/wp-settings.php on line 571