Remove unicorn reactions

[joshpuetz]

What type of PR is this? (check all applicable)

• [x] Refactor
• [ ] Feature
• [ ] Bug Fix
• [ ] Optimization
• [ ] Documentation Update

Description

This PR removes the unicorn reaction from articles. Users can not longer "unicorn" an article, nor will they see unicorn reactions in their statistic. Existing unicorn reactions are preserved, but not displayed. No summary data is recalculated, so reaction counts on articles with legacy unicorn reactions will be inaccurate.

Related Tickets & Documents

• Closes #18277

QA Instructions, Screenshots, Recordings

Just run locally

Added/updated tests?

• [x] Yes
• [ ] No, and this is why: please replace this line with details on why tests have not been included
• [ ] I need help with writing tests

[Forem core team only] How will this change be communicated?

Will this PR introduce a change that impacts Forem members or creators, the development process, or any of our internal teams? If so, please note how you will share this change with the people who need to know about it.

• [x] I've updated the Developer Docs or Storybook (for Crayons components)
• [ ] This PR changes the Forem platform and our documentation needs to be updated. I have filled out the Changes Requested issue template so Community Success can help update the Admin Docs appropriately.
• [ ] I've updated the README or added inline documentation
• [ ] I've added an entry to CHANGELOG.md
• [x] I will share this change in a Changelog or in a forem.dev post
• [ ] I will share this change internally with the appropriate teams
• [ ] I'm not sure how best to communicate this change and need help
• [ ] This change does not need to be communicated, and this is why not: please replace this line with details on why this change doesn't need to be shared

[optional] Are there any post deployment tasks we need to perform?

None

[optional] What gif best describes this PR or how it makes you feel?

[joshpuetz]

Setting to draft and marking as blocked as per conversation here: https://github.com/forem/forem/issues/18277#issuecomment-1239658500

TL;DR: we're pausing merging this PR until the replacement icon/widget for this space https://github.com/forem/forem/issues/18127, and will use a feature flag to toggle them.

[mirie]

@jaw6 can this one be closed?

[jaw6]

I think it's safe to close.