Remove metrics OTLP dataset config option

[estolfo]

What does this PR do?

Remove the otel.dataset metrics OTLP config option, as it needs to be logstash for the integration to work. We can add it back in the future if users ask for it.

Why is it important/What is the impact to the user?

Checklist

• 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 (and/or docker env variables)
• I have added tests that prove my fix is effective or that my feature works

Author's Checklist

• [ ]

How to test this PR locally

Related issues

• Related to Export metrics from Logstash via OTLP #19021
• Related to Build integration for Logstash metrics via OTLP #19022

Use cases

Screenshots

Logs

[github-actions]

🤖 GitHub comments

Just comment with:

• run docs-build : Re-trigger the docs validation. (use unformatted text in the comment!)
• run exhaustive tests : Run the exhaustive tests Buildkite pipeline.

[mergify]

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

• backport-8./d is the label to automatically backport to the 8./d branch. /d is the digit.
• If no backport is necessary, please add the backport-skip label

[github-actions]

🔍 Preview links for changed docs

• docs/reference/logstash-settings-file.md
• docs/reference/monitoring-with-opentelemetry.md

[github-actions]

✅ Vale Linting Results

No issues found on modified lines!

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[elasticmachine]

💔 Build Failed

• Buildkite Build
• Commit: 09eafd5

Failed CI Steps

• :rspec: Ruby unit tests
• :rspec: Ruby unit tests - FIPS mode
• :rspec: Ruby unit tests - FIPS mode
• :rspec: Ruby unit tests - FIPS mode
• :rspec: Ruby unit tests - FIPS mode
• :rspec: Ruby unit tests - FIPS mode
• :java: Java unit tests - FIPS mode
• 🥼 Integration Tests - FIPS mode / part 2-of-6
• 🥼 Integration Tests / part 4-of-6

History

• 💔 Build #4884 failed 07056d6
• 💔 Build #4883 failed dc8f6de