Make GHA refs validation check the whole branch name (OSOE-814)

[Piedone]

Currently, you can merge a PR without having the correct branch references in action/worfklow references, and Validate GitHub Actions Refs won't prevent this, if the target branch's name is a substring of the source branch (e.g. the target is task/gha-refs-validate-without-merge-queue and the source is task/gha-refs-validate-without-merge-queue-test-pr). This is most possibly due to using a pattern instead of an exact match.

This should be changed so the exact branch references are enforced.

This is not a huge issue currently, because the only branch we have it guarding is dev, and source branches will never be dev*.

Jira issue