Feature: Support for proprietary license

[takeda]

Feature

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Is your feature request related to a problem? Please describe

Currently when a proprietary license is defined, for example classifiers contains:
License :: Other/Proprietary License
The licensecheck results with unhelpful error

KeyError: <License.NO_LICENSE: 200

Describe the solution you'd like

Ideally licensecheck should just list licenses used by dependencies and mark licenses blacklisted in configuration.

Describe alternatives you've considered

As a workaround I can mark my project that it uses MIT license and get the output, but that forces me to provide false information in my project.

Additional context

[FredHappyface]

Just need to add proprietary license so I'll add that to the todo list

[FredHappyface]

Fixed in 746eace