HDFS-14487. Missing Space in Client Error Message (Contributed by Shweta Yakkali via Daniel Templeton)

Change-Id: I0f8ce74a35ab24fe94fd0e57d8247bb3fa575e6f

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DFSOutputStream.java

@@ -965,7 +965,7 @@ public class DFSOutputStream extends FSOutputSummer
         }
         try {
           if (retries == 0) {
-            throw new IOException("Unable to close file because the last block"
+            throw new IOException("Unable to close file because the last block "
                 + last + " does not have enough number of replicas.");
           }
           retries--;