Fix the unit test

Author: zsxwing

streaming/src/test/scala/org/apache/spark/streaming/UISeleniumSuite.scala

@@ -78,7 +78,7 @@ class UISeleniumSuite
 
         val h4Text = findAll(cssSelector("h4")).map(_.text).toSeq
         h4Text should contain("Active Batches (0)")
-        h4Text should contain("Completed Batches (0)")
+        h4Text should contain("Completed Batches (last 0 out of 0)")
 
         findAll(cssSelector("""#active-batches-table th""")).map(_.text).toSeq should be {
           List("Batch Time", "Input Size", "Scheduling Delay", "Processing Time", "Status")