End of Life announced for sass dependency.

[JDutil]

Ruby Sass is deprecated and will be unmaintained as of 26 March 2019. It would be good to consider changing the sass dependency to their suggested sassc-ruby or more likely sassc-rails library to ensure Solidus dependencies are maintained in the future.

Steps to reproduce

1. Uninstall sass gem: gem uninstall sass
2. Install sass gem: gem install sass

Expected behavior

No EOL messages for dependencies.

Actual behavior

Post-install message from sass:

Ruby Sass is deprecated and will be unmaintained as of 26 March 2019.

* If you use Sass as a command-line tool, we recommend using Dart Sass, the new
  primary implementation: https://sass-lang.com/install

* If you use Sass as a plug-in for a Ruby web framework, we recommend using the
  sassc gem: https://github.com/sass/sassc-ruby#readme

* For more details, please refer to the Sass blog:
  http://sass.logdown.com/posts/7081811

System configuration

Solidus Version: Master

Extensions in use: None