Add OpenSearch build script

[ankitkala]

Description

This change adds the changes required for the plugin to be built & published as part of opensearch.

Openserach-build PR: opensearch-project/opensearch-build#315
###Testing done

• brazil-build.
• verified by running the build workflow from opensearch-build repo. ./bundle-workflow/build.sh manifests/opensearch-1.1.0.yml --snapshot --component cross-cluster-replication
• Verified the artifact published for snapshot and release usecase.

Check List

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[dblock]

• Do you need build.sh? Looks suspiciously like the default one, except for the maven publication (is that required?). If you do, you can put build.sh into scripts/ to keep things better organized if you want.
• What are the file names from the output of assemble with and without -Dbuild.snapshot=?

[ankitkala]

• Do you need build.sh? Looks suspiciously like the default one, except for the maven publication (is that required?). If you do, you can put build.sh into scripts/ to keep things better organized if you want.
• What are the file names from the output of assemble with and without -Dbuild.snapshot=?

It is a replica of the default one. I added the script anticipating changes but ended up not making any change. So yes, it can be removed and we can rely on the default script.

Regarding the file names from assemble, opensearch-cross-cluster-replication-1.1.0-SNAPSHOT.zip and opensearch-cross-cluster-replication-1.1.0.zip is how the zip would be named.

[soosinha]

Removed build.sh

[dblock]

Is there no CI running on this repo? When the project i added to the distribution it cannot be breaking the build every day!

[soosinha]

@dblock PR for CI workflow: #123