Adding github action in ccr to publish snapshots to maven

[aggarwalShivani]

Description

Added a github action to publish plugin snapshots to maven. Followed guidelines as documented here
As this old #711 was closed without merging in main branch, trying to make similar changes now.

Related Issues

Resolves #1508

Tested by publishing to the local filesystem

ls -l snapshots/org/opensearch/plugin/opensearch-cross-cluster-replication/3.0.0.0-alpha1-SNAPSHOT/  | awk '{print $1, $9}'
total
-rw-r--r-- maven-metadata.xml
-rw-r--r-- maven-metadata.xml.md5
-rw-r--r-- maven-metadata.xml.sha1
-rw-r--r-- maven-metadata.xml.sha256
-rw-r--r-- maven-metadata.xml.sha512
-rw-r--r-- opensearch-cross-cluster-replication-3.0.0.0-alpha1-20250228.120739-1.pom
-rw-r--r-- opensearch-cross-cluster-replication-3.0.0.0-alpha1-20250228.120739-1.pom.md5
-rw-r--r-- opensearch-cross-cluster-replication-3.0.0.0-alpha1-20250228.120739-1.pom.sha1
-rw-r--r-- opensearch-cross-cluster-replication-3.0.0.0-alpha1-20250228.120739-1.pom.sha256
-rw-r--r-- opensearch-cross-cluster-replication-3.0.0.0-alpha1-20250228.120739-1.pom.sha512
-rw-r--r-- opensearch-cross-cluster-replication-3.0.0.0-alpha1-20250228.120739-1.zip
-rw-r--r-- opensearch-cross-cluster-replication-3.0.0.0-alpha1-20250228.120739-1.zip.md5
-rw-r--r-- opensearch-cross-cluster-replication-3.0.0.0-alpha1-20250228.120739-1.zip.sha1
-rw-r--r-- opensearch-cross-cluster-replication-3.0.0.0-alpha1-20250228.120739-1.zip.sha256
-rw-r--r-- opensearch-cross-cluster-replication-3.0.0.0-alpha1-20250228.120739-1.zip.sha512

Check List

• New functionality includes testing.
• New functionality has been documented.
• API changes companion pull request created.
• Commits are signed per the DCO using --signoff.
• Public documentation issue/PR created.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.
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[aggarwalShivani]

Hi @ankitkala
Requesting review on this change :)

[ankitkala]

Hi @ankitkala Requesting review on this change :)

Thanks for the changes @aggarwalShivani. LGTM!

[aggarwalShivani]

Thanks for the approval!

The github action has now got run and the plugin is published in the maven repo
https://aws.oss.sonatype.org/content/repositories/snapshots/org/opensearch/plugin/opensearch-cross-cluster-replication/3.0.0.0-alpha1-SNAPSHOT/opensearch-cross-cluster-replication-3.0.0.0-alpha1-20250304.093358-1.zip 🥳