HADOOP-17614. Bump netty to the latest 4.1.61. (#2850)

Reviewed-by: Ayush Saxena <ayushsaxena@apache.org>
(cherry picked from commit 29a6769b68f32fc3eb0686a955040b9412a24a66)

hadoop-project/pom.xml

@@ -142,7 +142,7 @@
     <htrace4.version>4.1.0-incubating</htrace4.version>
     <metrics.version>3.2.4</metrics.version>
     <netty3.version>3.10.6.Final</netty3.version>
-    <netty4.version>4.1.50.Final</netty4.version>
+    <netty4.version>4.1.61.Final</netty4.version>
     <snappy-java.version>1.1.8.2</snappy-java.version>
     <lz4-java.version>1.7.1</lz4-java.version>