Add mw back to review rotation

Author: michaelwoerister

triagebot.toml

@@ -913,7 +913,7 @@ cc = ["@kobzol"]
 [assign]
 warn_non_default_branch = true
 contributing_url = "https://rustc-dev-guide.rust-lang.org/getting-started.html"
-users_on_vacation = ["jyn514", "jhpratt", "oli-obk", "michaelwoerister"]
+users_on_vacation = ["jyn514", "jhpratt", "oli-obk"]
 
 [assign.adhoc_groups]
 compiler-team = [