Adding cron param for xtrabackup

Change-Id: Ifad8690991498103cd87884d7b1967e68b66acc9
Related: PROD-28173 (PROD:28173)
(cherry picked from commit cceafb932e4823dd6e17ac417938e937ae7a45e9)
diff --git a/xtrabackup/server/single.yml b/xtrabackup/server/single.yml
index ef5209a..d440e48 100644
--- a/xtrabackup/server/single.yml
+++ b/xtrabackup/server/single.yml
@@ -3,6 +3,7 @@
 parameters:
   xtrabackup:
     server:
+      cron: false
       backup_dir: /srv/volumes/backup/xtrabackup
       key:
         xtrabackup_pub_key: