fix: filter-by-commitish option in config

[jescalada]

Fixes filter-by-commitish option, and also counts as a bugfix which should trigger a 1.2.1 draft upon merging.

[github-actions]

Hi @jescalada! Thanks for the contribution.

I have a couple of requests to help us review and merge this PR:

Missing issue link: Could you please link this PR to an existing issue using "Fixes #N" or "Closes #N" in the description? If there isn't an issue yet, please create one describing the bug you're fixing. This helps us track the problem and ensures proper documentation.

More detail needed: Could you provide a bit more detail about what the filter-by-commitish option issue was and how you've fixed it? This will help reviewers understand the change and verify the fix is correct.

Thanks for mentioning that this should trigger a 1.2.1 draft release - that's helpful context!

[github-actions]

🔒 Automated Security Review

Security Review: No Issues Found

This PR adds a single configuration option (filter-by-commitish: true) to the GitHub release drafter configuration. No security concerns identified - this is a standard configuration change for release management tooling.