Revert "remove unneded escaping"

This reverts commit e2ec443a.

tasks/backups.yml

@@ -6,7 +6,7 @@
 - name: add gitlab-tar backup cronjob
   cron:
     name: gitlab-tar backup
-    job: 'umask 0077; /bin/tar -czf {{ gitlab.backup.path }}/$(date "+etc-gitlab-%s.tgz") -C / etc/gitlab'
+    job: 'umask 0077; /bin/tar -czf {{ gitlab.backup.path }}/$(date "+etc-gitlab-\%s.tgz") -C / etc/gitlab'
     special_time: daily
 - name: add gitlab backup cleanup job
   cron: