Release notes

[saratvemulapalli]

Add documentation support to have release notes standardized for all plugins

[saratvemulapalli]

Doc to release notes: https://github.com/opensearch-project/opensearch-plugins/blob/main/RELEASE_NOTES.md

[VijayanB]

@saratvemulapalli Can you confirm whether all plugins should have this corresponding file in their repository or we just need to ensure we follow this process?

[saratvemulapalli]

Its just a standard process and how release notes should look like.
You dont need to have similar files replicated in all the plugins.

[saratvemulapalli]

Closing this as we have added information on how release notes should be via: https://github.com/opensearch-project/opensearch-plugins/blob/main/STANDARDS.md#release-notes