Feature: Option to exclude packages from the report

[mckornfield]

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Feature Details

Allow excluding packages from being license crawled (i.e., showing up in the report at all)

Is your feature request related to a problem? Please describe

We have a few internal packages that show up as errors but since they're internal (pyproject.toml or an internal pypi) packages, that we don't have license information for; we just want to exclude them from the report
in general. However, ignore_packages just seems to "accept" their license information, but they still show up in the report

Describe the solution you'd like

Either reuse the ignore_packages option to control not showing them in the report, or add an option like exclude_packages which doesn't attempt to get any license information for these packages.

Describe alternatives you've considered

We considered patching the report or only running it in certain environments, but for now we just rely on the current output format where the licenses are blank.

Additional Context

I can add a sample set of pyproject.toml if needed