Update Maven workflow to trigger on release events and revert version to 2.2.0 in POM file

Author: reeshika-h

.github/workflows/maven--package-publish.yml

@@ -1,9 +1,6 @@
 name: Publishing to Maven Packages
 #on: [ push ]  # Trigger the workflow when a push (commit) event occurs
 on:
-  push:
-    branches:
-      - fix/workflow-release
   release:
     types: [ created ]
 jobs:

pom.xml

@@ -5,7 +5,7 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.contentstack.sdk</groupId>
     <artifactId>java</artifactId>
-    <version>2.2.0-beta</version>
+    <version>2.2.0</version>
     <packaging>jar</packaging>
     <name>contentstack-java</name>
     <description>Java SDK for Contentstack Content Delivery API</description>