[BUG] The Changelog Verifier GitHub Action runs 16 times and sends 16 emails if changelog is omitted

[dbwiddis]

What is the bug?

See description here:

• [BUG] The Changelog Verifier GitHub Action runs 26 times and sends 26 emails if changelog is omitted OpenSearch#13013

How can one reproduce the bug?

Submit a PR that does not need a change log, like #898 that I just submitted

What is the expected behavior?

One, or at most a number I can count on one hand, email informing me of my change log omission

What is your host/environment?

GitHub Actions

Do you have any screenshots?

Partial list shown...

Do you have any additional context?

15 of the 16 are because of the review_requested trigger and 15 individuals listed in CODEOWNERS
1 of the 16 was from the opened trigger, the only one that should probably matter here

See fix here:

• Reduce unnecessary duplication of changelog verifier GHA runs flow-framework#646