[BUG] Changlog is not updated by 'Dependabot PR actions' workflow when initially created for Dependabot PRs

[tlfeng]

Describe the bug
Please see #4547 (comment)

When dependabot PRs are initially created, the GHA workflow 'Dependabot PR actions' (https://github.com/opensearch-project/OpenSearch/blob/2.3.0/.github/workflows/dependabot_pr.yml#L51) will not update the changelog file.
Only ask dependabot to "recreate" the PR can solve the problem.

All the PRs created by dependabot on yesterday have got the problem: https://github.com/opensearch-project/OpenSearch/pulls?q=is%3Apr+label%3Adependabot+created%3A2022-09-19

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[kotwanikunal]

Please refer to the update on the comment here - #1868 (comment)

I have the change published at https://github.com/kotwanikunal/changelog-helper

[kotwanikunal]

Putting this on hold pending the discussion outcome from the proposal.