[FEATURE] Make raw JSON REST requests to OpenSearch

[dblock]

Is your feature request related to a problem?

Coming from opensearch-project/opensearch-clients#62, add support for making raw JSON requests.

What solution would you like?

1. If an existing mechanism exists, document it similar to Added a guide on making raw JSON REST requests. opensearch-py#542.
2. Add a high level DSL, e.g. client.get and client.post.

[Xtansia]

This exists in the low-level OpenSearch.Net client, but there's no high-level DSL wrapper. Example of its use can be seen here: #220 (comment)

[dblock]

await client.LowLevel.DoRequestAsync<VoidResponse>(
            HttpMethod.DELETE,
            "_search/point_in_time",
            CancellationToken.None,
            PostData.Serializable(new
            {
                pit_id = pitId
            }));

Nice. Documenting it would be a great start!

[Djcarrillo6]

Hi @Xtansia, I'd like to request assignment on this issue

[dblock]

Does it make sense to alias LowLevel to HTTP or http?

#406 (comment)

[Xtansia]

Does it make sense to alias LowLevel to HTTP or http?

#406 (comment)

A direct alias of LowLevel doesn't make much sense as it points to an instance of the full low-level client, meaning you'd get client.Http.Indices.PutTemplate.

I have some ideas for a high-level DSL for the http methods, that I'm going to look into feasibility for.