Update maven publishing workflow to accommodate nexus EOL

[gaiksaya]

Description

Maven central recently announced the end of life for publishing artifacts via nexus portal. As a part of the migration https://central.sonatype.org/pages/ossrh-eol/#process-to-migrate we made some changes to accommodate the new endpoints. See related PR

Also adds github repository condition for essential workflows else it keeps failing in the fork.

This PR accommodates the change to successfully publish artifacts to maven central in future releases.

Issues Resolved

part of opensearch-project/opensearch-build#5552

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[cwperks]

* What went wrong:
A problem occurred configuring root project 'opensearch-sdk-java'.
> Could not resolve all artifacts for configuration ':classpath'.
   > Could not resolve org.opensearch.gradle:build-tools:3.0.0-SNAPSHOT.
     Required by:
         project :
      > Dependency requires at least JVM runtime version 21. This build uses a Java 17 JVM.

This repo needs to be bumped to version 3.2.0 as well.