Docs: Clean up response test in getting_started

It had drifted from a fix applied to 5.x. The 5.x fix was more
readable. This applies the 5.x fix.

docs/reference/getting-started.asciidoc

@@ -216,8 +216,9 @@ And the response:
 epoch      timestamp cluster       status node.total node.data shards pri relo init unassign pending_tasks max_task_wait_time active_shards_percent
 1475247709 17:01:49  elasticsearch green           1         1      0   0    0    0        0             0                  -                100.0%
 --------------------------------------------------
-// TESTRESPONSE[s/0             0/0             [01]/]
-// TESTRESPONSE[s/1475247709 17:01:49  elasticsearch/\\d+ \\d+:\\d+:\\d+ docs_integTestCluster/ _cat]
+// TESTRESPONSE[s/1475247709 17:01:49  elasticsearch/\\d+ \\d+:\\d+:\\d+ docs_integTestCluster/]
+// TESTRESPONSE[s/0             0                  -/0             \d+                  -/]
+// TESTRESPONSE[_cat]
 
 We can see that our cluster named "elasticsearch" is up with a green status.