PHP notice when delete cache file for url with no trailing slash

I get this notice in my logs:

`Notice: Undefined index: path in /var/www/html/public/assets/plugins/nginx-helper/admin/class-purger.php on line 391`

This happens when the url is the homepage/only the domain, for example:
`http://mysite.localhost` or `http://example.com`

I believe the error is because `wp_parse_url` does not always return the key `PATH`.

