Add ssh-user to get_tripleo_ansible_inventory
Add ssh-user to get_tripleo_ansible_inventory

We were missing --ssh-user when calling
get_tripleo_ansible_inventory assigning
overcloud as the ssh_user by default.

This is failing after adding the --stack option
as he had only one before

Change-Id: I447a050ce67d626e7050a22c9821f883ebeda2ee
Closes-Bug: 1767379
Closes-Bug: 1769974

openstack/python-tripleoclient