Go-github: Support new "Delete Reactions" endpoints

[gmlewis]

GitHub Developer API announcement:
https://developer.github.com/changes/2020-02-26-new-delete-reactions-endpoints/

These new endpoints need to be supported:

• [x] Delete a commit comment reaction- #1445
  
  
  
  • DELETE /repos/:owner/:repo/comments/:comment_id/reactions/:reaction_id
  
  
  • Docs: https://developer.github.com/v3/reactions/#delete-a-commit-comment-reaction
  
  
• [x] Delete an issue reaction
  
  
  
  • DELETE /repos/:owner/:repo/issues/:issue_number/reactions/:reaction_id
  
  
  • Docs: https://developer.github.com/v3/reactions/#delete-an-issue-reaction
  
  
• [x] Delete a reaction to a commit comment
  
  
  
  • DELETE /repos/:owner/:repo/issues/comments/:comment_id/reactions/:reaction_id
  
  
  • https://developer.github.com/v3/reactions/#delete-an-issue-comment-reaction
  
  
• [x] Delete a pull request comment reaction
  
  
  
  • DELETE /repos/:owner/:repo/pulls/comments/:comment_id/reactions/:reaction_id
  
  
  • https://developer.github.com/v3/reactions/#delete-a-pull-request-comment-reaction
  
  
• [x] Delete team discussion reaction
  
  
  
  • DELETE /orgs/:org/teams/:team_slug/discussions/:discussion_number/reactions/:reaction_id
  
  
  • Docs: https://developer.github.com/v3/reactions/#delete-team-discussion-reaction
  
  
• [x] Delete team discussion comment reaction
  
  
  
  • DELETE /orgs/:org/teams/:team_slug/discussions/:discussion_number/comments/:comment_number/reactions/:reaction_id
  
  
  • Docs: https://developer.github.com/v3/reactions/#delete-team-discussion-comment-reaction
  
  

This would be a great PR for any new contributor to this repo or a new Go developer.
All contributions are greatly appreciated!

Feel free to volunteer for any issue and the issue can be assigned to you so that others don't attempt to duplicate the work.

Please check out our CONTRIBUTING.md guide to get started.

Thank you!

[wesleimp]

@gmlewis I could take it over

[gmlewis]

Thank you, @wesleimp! It is yours.

[gmlewis]

I neglected to mention that the existing "delete reactions" endpoint also needs to be deleted (assuming we implemented it... I'll have to check later).

[wesleimp]

I neglected to mention that the existing "delete reactions" endpoint also needs to be deleted (assuming we implemented it... I'll have to check later).

@gmlewis I'll delete the endpoint DeleteReactions when all these endpoints mentioned above are be supported. What do you think?

[gmlewis]

We typically add new endpoints and delete deprecated endpoints in the same PR so that the single issue (pointing to a blog post) can be fully closed and so that it can be more easily found.
But I'm actually fine to split the single issue up into ~two~ multiple PRs if you would prefer.

[wesleimp]

We typically add new endpoints and delete deprecated endpoints in the same PR so that the single issue (pointing to a blog post) can be fully closed and so that it can be more easily found.
But I'm actually fine to split the single issue up into ~two~ multiple PRs if you would prefer.

@gmlewis I prefer to split the issue in multiple PRs to make the review easier, but after the #1445 meged, I can close this issue in a single one. No problems to me

[ayzu]

I would like to take the second bullet point.

[gmlewis]

Thank you, @ayzu, but @wesleimp already signed up for the full issue.

[ayzu]

Oh, my bad:)

Thank you, @ayzu, but @wesleimp already signed up for the full issue.

[gmlewis]

No problem, @ayzu ! It's always better to have more volunteers than not enough! 😁