CI: Use ControlPersist and ControlMaster

Similar to [1].

[1]: https://review.opendev.org/c/openstack/openstack-ansible/+/851426

Change-Id: I254f71d607353e0cf4d3d5ebafd6813287c4fa9f

tests/templates/ansible.cfg.j2

@@ -10,3 +10,4 @@ inject_facts_as_vars = False
 [ssh_connection]
 pipelining = True
 retries = 3
+ssh_args = -C -o ControlMaster=auto -o ControlPersist=300