Remove changelog infrastructure in favor of centralized release notes automation

[ananzh]

Description

Remove the OSD-specific changelog workflow and fragment system, which was unique among all 160 opensearch-project repositories. Release notes will now be generated automatically by the opensearch-build team's centralized bot using PR labels and commit history. This cleanup eliminates manual changelog maintenance while standardizing the release notes process across the organization.

Issues Resolved

NA

Screenshot

NA

Testing the changes

NA

Changelog

• skip

Check List

• All tests pass
  • yarn test:jest
  • yarn test:jest_integration
• New functionality includes testing.
• New functionality has been documented.
• Update CHANGELOG.md
• Commits are signed per the DCO using --signoff

[Maosaic]

Do we need to remove the Changelog bot?

[github-actions]

PR Reviewer Guide 🔍

Here are some key observations to aid the review process:

🧪 No relevant tests

🔒 No security concerns identified

✅ No TODO sections

🔀 No multiple PR themes

⚡ Recommended focus areas for review Label Removal The skip-changelog label configuration was removed from the WhiteSource remediation settings. Verify that this label is no longer needed or that its removal won't affect any existing automation or PR workflows that may still reference it. "remediateSettings": { "workflowRules": { "enabled": true } }

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 61.58%. Comparing base (7782a80) to head (c393c9f).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #11563   +/-   ##
=======================================
  Coverage   61.58%   61.58%           
=======================================
  Files        4995     4995           
  Lines      137542   137542           
  Branches    23901    23901           
=======================================
  Hits        84707    84707           
+ Misses      46692    46691    -1     
- Partials     6143     6144    +1     

Flag	Coverage Δ
Linux_1	24.90% <ø> (ø)
Linux_2	39.42% <ø> (ø)
Linux_3	26.48% <ø> (+<0.01%)	⬆️
Linux_4	29.32% <ø> (-0.01%)	⬇️
Linux_5	39.36% <ø> (-0.01%)	⬇️

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[LDrago27]

@ananzh Should we test out the other opensearch-build team's centralized bot first , before removing the current system. Else it might be be too much work later to update the CHANGELOG file