Improve breaking change logic for changelog verifier

[jed326]

Description

Improve breaking change logic for changelog verifier

Related Issues

• Resolves [Feature Request] Changelog verifier should fail if CHANGELOG-3.0.MD is modified and a backport label is applied. #15155

Check List

• Functionality includes testing.
  - [ ] API changes companion pull request created, if applicable.
  - [ ] Public documentation issue/PR created, if applicable.

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[github-actions]

❌ Gradle check result for 5b0d901: FAILURE

Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green. Is the failure a flaky test unrelated to your change?

[jed326]

For testing see:

• https://github.com/opensearch-project/OpenSearch/actions/runs/10360248403/job/28678317869?pr=15214
• https://github.com/opensearch-project/OpenSearch/actions/runs/10360303513/job/28678465760?pr=15214

[jed326]

@andrross @sandeshkr419 could you help review? Thanks!

[opensearch-trigger-bot]

The backport to 2.x failed:

The process '/usr/bin/git' failed with exit code 128

To backport manually, run these commands in your terminal:

# Navigate to the root of your repository
cd $(git rev-parse --show-toplevel)
# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add ../.worktrees/OpenSearch/backport-2.x 2.x
# Navigate to the new working tree
pushd ../.worktrees/OpenSearch/backport-2.x
# Create a new branch
git switch --create backport/backport-15214-to-2.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 2defb76f8bb0d53714804963b5f155730a1825d8
# Push it to GitHub
git push --set-upstream origin backport/backport-15214-to-2.x
# Go back to the original working tree
popd
# Delete the working tree
git worktree remove ../.worktrees/OpenSearch/backport-2.x

Then, create a pull request where the base branch is 2.x and the compare/head branch is backport/backport-15214-to-2.x.

[peternied]

@jed326 Can you look into what change wasn't backported and then retrigger this workflow once that's done?

[jed326]

Thanks @peternied, I realized that we probably don't want to backport this since changelog-3.0 doesn't exist on 2.x branch