Previously, we used the schema type "DiscussionForumPosting" for all the posts including replies. This is not recommended as per Google search experts. This commit changes the schema type to "Comment" for replies.
This simplifies the crawler-linkback-list to only be a point of reference to the actual DiscussionForumPosting objects.
See "Summary page": https://developers.google.com/search/docs/advanced/structured-data/carousel?hl=en#summary-page
> [It] defines an ItemList, where each ListItem has only three properties: @type (set to ListItem), position (the position in the list), and url (the URL of a page with full details about that item).
