triagebot: Treat I-*nominated like I-nominated

rustbot doesn't allow unauthenticated users to set `I-nominated`; apply
the same permissions to the new `I-*nominated` labels.

Author: joshtriplett

triagebot.toml

@@ -5,8 +5,8 @@ allow-unauthenticated = [
     "requires-nightly",
     "regression-*",
     "perf-*",
-    # I-* without I-nominated
-    "I-*", "!I-nominated",
+    # I-* without I-*nominated
+    "I-*", "!I-*nominated",
     "AsyncAwait-OnDeck",
 ]