Updated openstack/openstack
Project: openstack/tempest  7d5c93f561682db6303a0f89930c3d6fd6d0f5fe
null
Up the default timeout for stack builds

This commit ups the default stack build timeout from 600 to 1200.
The stack frequently can take longer than 600 secs to build so
doubling it should give us a safe margin.

Related-Bug: #1297560

Change-Id: I3b13a225793d42e2fa9f4871b2fe81c745954c56