Add a "Show all packages" filter to the HTML output

[hogo6002]

#1611 added license scanning results to the HTML output, but the current filter logic hides all packages without vulnerabilities. As a result, most packages with license violations are hidden and cannot be viewed.

To resolve this, we can add a filter to the HTML output to display packages with license violations even if they have no vulnerabilities (the filter logic determining which packages to hide needs to be updated).

[github-actions]

This issue has not had any activity for 60 days and will be automatically closed in two weeks

See https://github.com/google/osv-scanner/blob/main/CONTRIBUTING.md for how to contribute a PR if you're interested in helping out.