Fix Fandom recent change in API

src/bot.py

@@ -464,6 +464,8 @@ async def discussion_handler():
 						comment_events = []
 						targets = await generate_targets(db_wiki["wiki"], "AND NOT postid = '-1'")
 						for post in discussion_feed:
+							if not post:
+								continue
 							if post["_embedded"]["thread"][0]["containerType"] == "ARTICLE_COMMENT" and post["id"] > db_wiki["postid"]:
 								comment_events.append(post["forumId"])
 						comment_pages: dict = {}