code: func (s *ChangesService) DeleteVote(changeID string, accountID string, label string, input *DeleteVoteInput) (*Response, error) {
  	u := fmt.Sprintf("changes/%s/reviewers/%s/votes/%s", changeID, accountID, label)
  	return s.client.DeleteRequest(u, input)
  }
docs: // DeleteVote deletes a single vote from a change. Note, that even when the
  // last vote of a reviewer is removed the reviewer itself is still listed on
  // the change.
  //
  // Gerrit API docs: https://gerrit-review.googlesource.com/Documentation/rest-api-changes.html#delete-vote