List thread participants
Fetch the participants for a thread with paging.
Endpoints
GET /api/v1/teams/{team_slug}/repos/{repo_slug}/threads/{number}/participants
GET /api/v1/users/{username}/repos/{repo_slug}/threads/{number}/participants
Success
200 OK with a paged response containing
participant_username, participant_rank, and
participant_count. Results are ordered by first participation in
the thread, with the thread creator first.