Deprecation warning while making a commit

Please see the following tips:

```bash
markdownlint-cli2 v0.4.0 (markdownlint v0.25.1)
(node:32743) [DEP0040] DeprecationWarning: The `punycode` module is deprecated. Please use a userland alternative instead.
(Use `node --trace-deprecation ...` to show where the warning was created)
```