chore: update .dockerignore

[suguanYang]

Summary

• describe the change
• describe any API, worker, deployment, or migration impact
• link the related issue or task

Verification

• list the commands you ran
• list any manual API, worker, or local-dev checks you performed
• note anything intentionally not tested

Deployment Notes

• note new or changed environment variables
• note database migrations, queue changes, storage changes, or release-order requirements
• note backwards compatibility or rollback concerns

Checklist

• Tests were added or updated when behavior changed
• Public docs, examples, or OpenAPI contracts were updated when needed
• Database migrations are idempotent and safe to deploy
• Logs, errors, and validation paths avoid leaking secrets or user data
• The pull request description explains any breaking or user-visible change