Add parse argument of destination configuration file (#5203)

scripts/migrate.py

@@ -201,6 +201,7 @@ class ObjMigrateWorker(Thread):
 def main(argv):
     parser = argparse.ArgumentParser()
     parser.add_argument('--decrypt', action='store_true', help='decrypt data from source storage and write to destination in plain text')
+    parser.add_argument('config_dir', help='The dir where the destination configuration file exists')
     args = parser.parse_args()
 
     decrypt = args.decrypt