Replace apm-server OTLP endpoint with Otel native processors and Elasticsearch

[rogercoll]

Changes

Please provide a brief description of the changes here.

Merge Requirements

For new features contributions, please make sure you have completed the following
essential items:

• CHANGELOG.md updated to document new feature additions
• Appropriate documentation updates in the docs
• Appropriate Helm chart updates in the helm-charts

Maintainers will not merge until the above have been completed. If you're unsure
which docs need to be changed ping the
@open-telemetry/demo-approvers.

[jasonrhodes]

Thanks for adding this! A few questions off the bat

• What is EDOT
• Where does the APM server we are currently using fit into this?
• Receivers, connectors, processors, exporters - these are all generic OTEL concepts that can be read about in the OTEL docs, is that right?
  • Do we provide custom Elastic versions of any of these, and if so do we have docs for those as well, especially configuration?
• How do these components map to configurations and env variables and config overrides? (This might not be appropriate for this diagram but it's something that comes up a lot)