A workflow on pull_request has branches: [release]. A pull request from feature/payments to main does not run. The author says the source branch should satisfy the filter. Which interpretation is correct?

1. For pull_request, the branches filter applies to the base branch, so this pull request does not match release.
2. Every pull_request event bypasses branch filtering if the workflow file is valid.
3. Replace branches with tags: [release] under pull_request to select the base branch.
4. Treat branches as a source-branch filter and expect feature/payments to match a release base.