Update ES version (#5)

Author: sp-gupta

pom.xml

@@ -37,7 +37,7 @@
     </scm>
 
     <properties>
-        <es.version>7.17.21</es.version>
+        <es.version>7.17.23</es.version>
         <hamcrest.version>1.3</hamcrest.version>
         <mockito.version>2.28.2</mockito.version>
         <gson.version>2.9.0</gson.version>