fix output redirection

tasks/gitlab.yml

@@ -43,6 +43,6 @@
   - name: add ldap group sync cronjob
     cron:
       name: gitlab ldap group membership sync
-      job: "/usr/local/bin/gitlab-ldap-groupsync.py > /dev/null &2>/dev/null"
+      job: "/usr/local/bin/gitlab-ldap-groupsync.py > /dev/null 2>&1"
       minute: "12,27,42,57"