Include effective ES output config in the Beats diagnostics

[faec]

The Beats diagnostics should include the final effective config for the Elasticsearch output, after the presets have been applied.

With the addition of performance presets, the final effective configuration for the Elasticsearch output will look different than the raw component config set by Agent, since one preset flag can set/override several other flags in the output. It is still possible in theory to determine the effective configuration, since it is uniquely determined by the preset flag, but it could be overlooked during troubleshooting, and may be harder in the future since the preset values may change between versions. Including the final effective config gives an easy way to confirm the settings that the output was actually using.

[elasticmachine]

Pinging @elastic/elastic-agent-data-plane (Team:Elastic-Agent-Data-Plane)

[botelastic[bot]]

Hi! We just realized that we haven't looked into this issue in a while. We're sorry!

We're labeling this issue as Stale to make it hit our filters and make sure we get back to it as soon as possible. In the meantime, it'd be extremely helpful if you could take a look at it as well and confirm its relevance. A simple comment with a nice emoji will be enough :+1. Thank you for your contribution!