include salt application files for cassandra and zookeeper

PROD-17856

Change-Id: Id8583901a76c7032df2e3187f689cd067d1bc821
diff --git a/cassandra/backup/client/single.yml b/cassandra/backup/client/single.yml
index 90fdc5d..892f92f 100644
--- a/cassandra/backup/client/single.yml
+++ b/cassandra/backup/client/single.yml
@@ -1,4 +1,5 @@
 classes:
+- service.cassandra.backup.client
 - system.openssh.client.root
 parameters:
   _param: