Bug 1642317 - add ast (Asturian) to calendar l10n.toml since not matching the Thunderbird l10n.toml is now an error. r=rjl

Otherwise we get: RuntimeError: File "chrome/calendar/calendar-alarms.properties" not found in /builds/worker/workspace/obj-build/comm/mail/locales/merge-dir/ast/calendar

calendar/locales/l10n.toml

@@ -7,6 +7,7 @@ basepath = "../.."
 locales = [
     "af",
     "ar",
+    "ast",
     "be",
     "bg",
     "br",