Please add documentation for config options

[pingram3030]

The problem

I have wasted hours searching the internet for how to configure things like TLS config because there was doc of all of the available plugin options. I just found out that it can sniff cluster nodes and that I can change the maximum _bulk size to reduce the incidence I have of packets being oversized.

The solution

Link to the api_configs file as it already contains appropriate comments.

https://github.com/opensearch-project/logstash-output-opensearch/blob/main/lib/logstash/plugin_mixins/opensearch/api_configs.rb

[andrross]

Catch All Triage - 1 2

[dlvenable]

Fixed by #275.