Add pluginJar publication to publish to org.opensearch group

[cwperks]

Description

Opening this up as a draft PR while testing the change. I believe its possible to add a section in the publication area of the build.gradle to publish the jar for opensearch-job-scheduler to the org.opensearch group.

Issues Resolved

Attempts to fix: #374

Check List

• New functionality includes testing.
  • All tests pass
• New functionality has been documented.
  • New functionality has javadoc added
• Commits are signed per the DCO using --signoff

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