Dependencies must be prefixed

All dependencies must be prefixed by project name, So please apply new {project}:{module} format for dephttps://www.drupal.org/docs/8/creating-custom-modules/let-drupal-8-know-... in info.yml filehttps://www.drupal.org/docs/8/creating-custom-modules/let-drupal-8-know-about-your-module-with-an-infoyml-file

It is supported since 8.0 and 7.40 Change Record: Project namespaces can now be added for module dependencies, and is now a Best Practice Define project dependencies in core module .info files).

It is useful for Installation profiles to work well. So sooner is better.
Hope this helps.