Use MD_STD::mkdir in MDOutputHandler

src/MDOutputHandler.php

@@ -45,7 +45,7 @@ public function flush_to_logfile():void {
         if ($this->_logfile_status_checked === false) {
 
             if (!\is_dir(__DIR__ . "/../logs")) {
-                \mkdir(__DIR__ . "/../logs", 0775);
+                MD_STD::mkdir(__DIR__ . "/../logs", 0775);
             }
 
             \touch($this->_logfile);