Ignore variable column widths in ovsdb functional tests

The ovsdb tests check the output of "ovsdb-client monitor" before and after
some operations. The first line of output is a header row with spaces for
column separation. The column widths can vary depending on the data in the
columns, so compress multiple spaces to one for testing.

Change-Id: I6b4690ea9ef1c1b215411ca2c39b1e65fec2c6c7
Partial-bug: #1336172

neutron/tests/functional/agent/linux/test_ovsdb_monitor.py

@@ -66,7 +66,10 @@ class TestOvsdbMonitor(BaseMonitorTest):
         while True:
             output = list(self.monitor.iter_stdout())
             if output:
-                return output[0]
+                # Output[0] is header row with spaces for column separation.
+                # The column widths can vary depending on the data in the
+                # columns, so compress multiple spaces to one for testing.
+                return ' '.join(output[0].split())
             eventlet.sleep(0.01)
 
     def test_killed_monitor_respawns(self):