Update .github/release.yml to exclude bot accounts from GitHub release notes

[eason9487]

Changes proposed in this Pull Request:

This PR update .github/release.yml to exclude bot accounts from GitHub release notes.

Originally, PRs created by the github-actions bot would not have been included, but they have been recently.

Checks:

• Does your code follow the WordPress coding standards?
• Have you written new tests for your changes, as applicable?
• Have you successfully run tests with your changes locally?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

Changelog entry