[system tests] Thread 1 on Ubuntu for 5.0 timed out

http://jenkins-product.srt.mirantis.net:8080/view/5.0_swarm/job/5.0_fuelmain.system_test.ubuntu.thread_1/43/consoleFull
 def check_ceph_partitions_after_reboot(self):
"""Check that Ceph OSD partitions are remounted after reboot

        Scenario:
            1. Create cluster
            2. Add 1 node with controller role
            3. Add 1 node with compute and Ceph OSD roles
            4. Add 1 node with Ceph OSD role
            5. Deploy the cluster
            7. Check Ceph status
            8. Read current partitions
            9. Warm-reboot Ceph nodes
            10. Read partitions again
            11. Check Ceph health
            12. Cold-reboot Ceph nodes
            13. Read partitions again
            14. Check Ceph health

Slave-3 do not start after warm retsart during 480 minutes and job was aborted by timeout.

I beleive that tests should handle such situation (set timeout here
for node in devops_nodes:
            wait(
                lambda: self.get_nailgun_node_by_devops_node(node)['online'])
 ) and do not wait while jenkins aborted job by timeout