Provide a 'Changelog' link on rubygems.org/gems/chartkick

[mark-young-atg]

By providing a 'changelog_uri' in the metadata of the gemspec a 'Changelog' link will be shown on https://rubygems.org/gems/chartkick which makes it quick and easy for someone to check on the changes introduced with a new version.

Details of this functionality can be found on https://guides.rubygems.org/specification-reference/

[ankane]

Hi @mark-young-atg, thanks for the PR, but it's not something I'd like to add.

[mark-young-atg]

Hi @ankane , thanks for the update. Would you mind explaining why? I'm not sure what the downside is.