feat!: remove Elastic Trace processor from EDOT Collector

[andrzej-stencel]

What does this PR do?

Removes the Elastic Trace processor from EDOT Collector, replacing all usages with its direct drop-in replacement, the Elastic APM processor.

Why is it important?

The Elastic Trace processor was deprecated and its code was removed in elastic/opentelemetry-collector-components#784.

Checklist

• I have read and understood the pull request guidelines of this project.
• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works
• I have added an entry in ./changelog/fragments using the changelog tool
• [ ] I have added an integration test or an E2E test

Disruptive User Impact

This is a breaking change for users if they use the processor in their EDOT Collector configurations.

The fix is simple: replace elastictrace with elasticapm in their configurations.

How to test this PR locally

go build .
sudo ./elastic-aget otel components

[mergify]

This pull request does not have a backport label. Could you fix it @andrzej-stencel? 🙏
To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-./d./d is the label that automatically backports to the 8./d branch. /d is the digit
• backport-active-all is the label that automatically backports to all active branches.
• backport-active-8 is the label that automatically backports to all active minor branches for the 8 major.
• backport-active-9 is the label that automatically backports to all active minor branches for the 9 major.

[github-actions]

🔍 Preview links for changed docs

• docs/reference/edot-collector/config/default-config-standalone.md
• docs/reference/edot-collector/config/tail-based-sampling.md

[theletterf]

Thanks!

Please revert the changes in components.md and custom-collector.md, since those docs are meant to show the latest stable release (9.1.5) and will update automatically upon 9.2 release.

I would also recommend to edit all the other sample configurations and backport (forwardport?) the changes to the cut 9.2 branch.

[elasticmachine]

Pinging @elastic/elastic-agent-control-plane (Team:Elastic-Agent-Control-Plane)

[andrzej-stencel]

Please revert the changes in components.md and custom-collector.md, since those docs are meant to show the latest stable release (9.1.5) and will update automatically upon 9.2 release.

Right, fixed in 56127ab.

[elasticmachine]

💚 Build Succeeded

• Buildkite Build
• Commit: 6075811

cc @andrzej-stencel

[ChrsMark]

@gregkalapos mind taking a look too?

[gregkalapos]

We just had a zoom call with @andrzej-stencel and @AlexanderWert and concluded that removing this processor would be a breaking change, which we'd like to avoid.

On the other hand, the code of the elastic trace processor is already removed from the collector components repo, so the last version depends on older upstream components, which makes bumping versions harder - so this would have not worked probably anyways as it was in this repo.

Plan is that I'll try to create a small processor with the same name elastictraceprocessor in the component repo, which just forwards to the new elasticapmprocessor. But if we want to avoid breaking changes, we'll need a follow up PR and add back elastictraceprocessor with the new version.