[DOC] New Paginated _list APIs (_list/indices and _list/shards) in Opensearch

[gargharsh3134]

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• Request a change to existing documentation
• Add new documentation
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Tell us about your request. Provide a summary of the request.
Documentation changes required for newly introduced _list APIs (namely _list/indices and _list/shards). These new APIs serve as a paginated alternate to existing _cat/indices and _cat/shards APIs. _list/indices and _list/shards APIs, will continue to support all the query parameters which are currently supported by the _cat counterparts, along with 3 new additional parameters, namely:
next_token, size and sort

*Version: 2.18 and onwards.

What other resources are available? Provide links to related issues, POCs, steps for testing, etc.
opensearch-project/OpenSearch#14258
opensearch-project/OpenSearch#14257