replace os.system(mkdir) with os.mkdir

clone.py

@@ -16,7 +16,7 @@ class Cloner:
     def handleDir(self, dirPath: str):
         backupDirPath = dirPath.replace(self.targetDir, self.backupDir)
         if not os.path.isdir(backupDirPath):
-            os.system('mkdir {path}'.format(path=backupDirPath))
+            os.mkdir(backupDirPath)
         with os.scandir(dirPath) as it:
             for entry in it:
                 if entry.is_dir():