Fix shell for keystone user for rsync to work

Fix shell for keystone user to /bin/bash for rsync to work
between control nodes for fernet and credential keys sync.
Generally keystone should be created by linux formula since user
definition is present in reclass

Change-Id: I6ed8e28849ef00804fae9af3b77a83778dcf1972
Related-PROD: PROD-22887
1 file changed