License as enum type

[ildyria]

Use proper enum type instead of array of values..

Extracted from Livewire branch :)

[codecov]

Codecov Report

Merging #2025 (daf5010) into master (5f00cbb) will decrease coverage by 0.39%.
The diff coverage is 79.72%.

Additional details and impacted files

[SerenaButler]

I got an error on my gallery page: "CC-BY-NC-ND" is not a valid backing value for enum "App\Enum\LicenseType"

I added "case CC_BY_NC_ND = 'CC-BY-NC-ND';" and "self::CC_BY_NC_ND->value => 'CC Attribution-NonCommercial-NoDerivatives'," and it is working again.