TEZ-4409: Upgrade async-http-client to 2.12.3 to resolve CVE (#204) (D M Murali Krishna Reddy reviewed by Laszlo Bodor)

diff --git a/pom.xml b/pom.xml
index 9ed00c9..1a51c6a 100644
--- a/pom.xml
+++ b/pom.xml
@@ -243,7 +243,7 @@
       <dependency>
         <groupId>org.asynchttpclient</groupId>
         <artifactId>async-http-client</artifactId>
-        <version>2.12.1</version>
+        <version>2.12.3</version>
         <exclusions>
           <exclusion>
             <groupId>io.netty</groupId>