message: Fix `preview-hidden-comments` on review comments
diff: /* Truncate hidden comment preview text with ellipsis */
  -.rgh-preview-hidden-comments :is(.discussion-item-copy, .timeline-comment-header-text) {
  +.rgh-preview-hidden-comments :is(.timeline-comment-header-text, summary h3) {
  overflow: hidden;
  white-space: nowrap;
  text-overflow: ellipsis;
  