GraphQL schema update

[github-actions]

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The GraphQL schema has been updated and relay-compiler has been re-run on the package source. relay-compiler failed with the following output:

Writing js
ERROR:
Encountered 5 errors:
- Unknown field 'users' on type '[ReactionGroup!]'.
  
  mutations/add-reaction.js:8:11
  7 |           viewerHasReacted
  8 |           users {
    |           ^
  9 |             totalCount
- Unknown field 'position' on type 'PullRequestReviewComment'.
  
  containers/accumulators/review-comments-accumulator.js:33:13
  32 |             path
  33 |             position
     |             ^
  34 |             createdAt
- Unknown field 'position' on type 'PullRequestReviewComment'.
  
  mutations/add-pr-review-comment.js:17:11
  16 |           path
  17 |           position
     |           ^
  18 |           createdAt
- Unknown field 'users' on type '[ReactionGroup!]'.
  
  mutations/remove-reaction.js:8:11
  7 |           viewerHasReacted
  8 |           users {
    |           ^
  9 |             totalCount
- Unknown field 'users' on type '[ReactionGroup!]'.
  
  views/emoji-reactions-view.js:7:9
  6 |         viewerHasReacted
  7 |         users {
    |         ^
  8 |           totalCount

🚨 Check out this branch to fix things so we don't break. 🚨