Upgrade Gson dependency to version 2.8.9

Change-Id: Ifd3fb9ec6ebfc8874bb799bc198219511fe55a2f

Update pom.xml

Update pom.xml

Author: medb

hadoop-project/pom.xml

@@ -138,7 +138,7 @@
     <jdom.version>1.1</jdom.version>
     <jna.version>5.2.0</jna.version>
     <grizzly.version>2.2.21</grizzly.version>
-    <gson.version>2.2.4</gson.version>
+    <gson.version>2.8.9</gson.version>
     <metrics.version>3.2.4</metrics.version>
     <netty3.version>3.10.6.Final</netty3.version>
     <netty4.version>4.1.68.Final</netty4.version>