Menu entries with <nolink> paths are rendered as empty <a> hrefs

Working on it.

Fixed the issue by modifying the twig files.

- Added checks to see if the url has a link or no link at all.
- Modified few manual tags to the drupal twig link() filter for better code optimization and automatic handling of the given issue :)

Please review the changes and check if the issue has been fixed or not.

Note: Since drupal twigs link() filter does not allow extra html tags in its text, so I have not changed those links which have other html tags inside the tags.