Update bad looking 'diff' code blocks with 'markdown' (#6152)

Co-authored-by: Jakub Kuczys <me@jacken.men>

redbot/cogs/trivia/session.py

@@ -279,10 +279,10 @@ class TriviaSession:
 
     async def send_table(self):
         """Send a table of scores to the session's channel."""
-        table = "+ Results: \n\n"
+        table = "Results:\n\n"
         for user, score in self.scores.most_common():
             table += "+ {}\t{}\n".format(user, score)
-        await self.ctx.send(box(table, lang="diff"))
+        await self.ctx.send(box(table, lang="markdown"))
 
     def stop(self):
         """Stop the trivia session, without showing scores."""