MM-35297 Add the ability to control if thread is followed when marking post as unread and don't autofollow from API (#17799)

* Add the ability to control if thread is followed when marking post as unread and don't autofollow from API

* Fix style

api4/post.go

@@ -657,7 +657,7 @@ func setPostUnread(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	state, err := c.App.MarkChannelAsUnreadFromPost(c.Params.PostId, c.Params.UserId, collapsedThreadsSupported)
+	state, err := c.App.MarkChannelAsUnreadFromPost(c.Params.PostId, c.Params.UserId, collapsedThreadsSupported, false)
 	if err != nil {
 		c.Err = err
 		return