Remove [no-mentions] handler in our triagebot config

https://github.blog/changelog/2025-11-07-removing-notifications-for-mentions-in-commit-messages/

Author: Urgau

library/compiler-builtins/triagebot.toml

@@ -12,10 +12,6 @@ exclude_titles = ["Rustc pull update"]
 [issue-links]
 check-commits = false
 
-# Prevents mentions in commits to avoid users being spammed
-# Documentation at: https://forge.rust-lang.org/triagebot/no-mentions.html
-[no-mentions]
-
 # Enable issue transfers within the org
 # Documentation at: https://forge.rust-lang.org/triagebot/transfer.html
 [transfer]