Always sync time for master node after revert

During migration to keystone shared session we gon an issue when
time on master node was changed (during ntp sync). This issue reproduces only
for the first connection after time sync.

Change-Id: I2f203b8a1957b70389e76f9fa99459b1365b242f
Related-bug:1606887

fuelweb_test/models/environment.py

@@ -309,6 +309,8 @@ class EnvironmentModel(object):
 
         if not skip_timesync:
             self.sync_time()
+        else:
+            self.sync_time(['admin'])
         try:
             with QuietLogger(upper_log_level=logging.CRITICAL):
                 # TODO(astudenov): add timeout_msg