[DOC]Grouping Top N queries by latency and resource usage

[deshsidd]

What do you want to do?
Need to add documentation for the grouping Top N by latency and resource usage feature :
opensearch-project/OpenSearch#13357
opensearch-project/query-insights#66

• Request a change to existing documentation
• Add new documentation
• Report a technical problem with the documentation
• Other

Tell us about your request. Provide a summary of the request.

*Version: List the OpenSearch version to which this issue applies, e.g. 2.14, 2.12--2.14, or all.

What other resources are available? Provide links to related issues, POCs, steps for testing, etc.