heartbeat: fix 'realtive' spelling typo in browser timing field description

[strawgate]

Summary

Fix a spelling typo in the heartbeat browser timing field description.

• heartbeat/_meta/fields.common.yml: realtive → relative
• Corresponding generated docs updated

Closes partial #49496

Test plan

• Verify corrected field description text

[github-actions]

🤖 GitHub comments

Just comment with:

• run docs-build : Re-trigger the docs validation. (use unformatted text in the comment!)

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

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Run ID: 0861bd06-9390-48f2-8763-db6d82bdad3e

📥 Commits

Reviewing files that changed from the base of the PR and between 884e58d and 4fd74fd.

📒 Files selected for processing (5)

• changelog/fragments/1774377534-fix-typos-heartbeat-browser-fields.yaml
• docs/reference/heartbeat/exported-fields-browser.md
• heartbeat/_meta/fields.common.yml
• heartbeat/docs/fields.asciidoc
• heartbeat/include/fields.go

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📝 Walkthrough

Walkthrough

This pull request corrects a spelling error across the heartbeat documentation and configuration files. The misspelling "realtive" is replaced with "relative" in the description of the browser.relative_trace field. The changes span four files: a new changelog fragment documenting the bug fix, the exported fields reference documentation, the common fields YAML configuration file, and the AsciiDoc documentation. No structural changes, field definitions, or code modifications are included—only descriptive text corrections.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

• 🛠️ Update Documentation: Commit on current branch
• 🛠️ Update Documentation: Create PR

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[elasticmachine]

Pinging @elastic/obs-ds-hosted-services (Team:obs-ds-hosted-services)

[vishaangelova]

LGTM!

[vishaangelova]

Actually, this needs to be backported to 9.3 for the changes to be published to the docs site (we publish from the latest minor branch).