releng_common: Fix invalid exception for anonymous users.
releng_common: Fix invalid exception for anonymous users.

mozilla-releng/services,lundjordan/services,lundjordan/services,garbas/mozilla-releng-services,andrei987/services,lundjordan/services,srfraser/services,lundjordan/services,garbas/mozilla-releng-services,srfraser/services,mozilla-releng/services,La0/mozilla-relengapi,La0/mozilla-relengapi,srfraser/services,mozilla-releng/services,garbas/mozilla-releng-services,andrei987/services,mozilla-releng/services,La0/mozilla-relengapi,srfraser/services,andrei987/services,andrei987/services,garbas/mozilla-releng-services,La0/mozilla-relengapi