UHF-X: Fix list of links item heading level

[Arkkimaagi]

UHF-X

Siteimprove reports mixed heading levels on pages that do not have h2 and contain list-of-links with no title. (h1 --> h3) For example: Symppis

What was done

• A check was added to list-of-links for paragraph title that toggles h2 or h3 level for links.

How to install

• Make sure your instance is up and running on latest dev branch.
  • git pull origin dev
  • make fresh
• Update the HDBT theme
  • composer require drupal/hdbt:dev-UHF-X_list_of_links_h_level
• Run make drush-cr

How to test

• Check that list of links item heading levels work with and without paragraph title (either h3 or h2)
• Check that code follows our standards

Designers review

• This PR does not need designers review

[khalima]

Works nicely! 🚀