Latest OpenSearch fails during index creation due to deprecation

After adding the latest opensearch version to weekly pipelines, we are seeing failures for the latest opensearch version due to a deprecation:

#539894 (closed)

Elasticsearch::Transport::Transport::Errors::BadRequest:
  [400] {"error":{"root_cause":[{"type":"mapper_parsing_exception","reason":"Failed to parse mapping [_doc]: nmslib engine is deprecated in OpenSearch  and cannot be used for new index creation in OpenSearch from  3.0.0."}],"type":"mapper_parsing_exception","reason":"Failed to parse mapping [_doc]: nmslib engine is deprecated in OpenSearch  and cannot be used for new index creation in OpenSearch from  3.0.0.","caused_by":{"type":"illegal_argument_exception","reason":"nmslib engine is deprecated in OpenSearch  and cannot be used for new index creation in OpenSearch from  3.0.0."}},"status":400}

We need to ensure the latest version of OS keeps working in case Self-Managed or Dedicated upgrade to this version.

Please also see https://github.com/opensearch-project/k-NN/pull/2573 for the related breaking change in OpenSearch 3.0.0.