List alternatives on the module page

Problem/Motivation

Hi, thanks for the great module!

For evaluation, it would be great to list similar modules on the module page:

• https://www.drupal.org/project/anti_duplicates
• https://www.drupal.org/project/allow_only_one
• https://www.drupal.org/project/field_validation
• https://www.drupal.org/project/unique_field
• https://www.drupal.org/project/unique_field_ajax
• https://www.drupal.org/project/unique_content_field_validation
• https://www.drupal.org/project/unique_entity_title
• https://www.drupal.org/project/suggest_similar_titles

What do you think makes sense to list?

Steps to reproduce

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes