Reduce Rails dependencies

[orien]

rails_autolink declares a runtime dependency on rails. This brings in transitive dependencies like actioncable, activerecord, and activestorage. These aren't strictly necessary to use rails_autolink.

I propose to reduce the declared runtime dependencies by replacing rails with actionview, activesupport, and railties. This will give downstream projects the ability to be more selective in the Rails dependencies they use.

[amatsuda]

@orien Do you have any idea why the CI is passing although we're still requiring rails in test/test_rails_autolink.rb#L4?

[orien]

@amatsuda Thanks for the thorough review 🙇

The require 'rails' statement is actually satisfied by the railties gem. See: https://github.com/rails/rails/blob/7-0-stable/railties/lib/rails.rb

[amatsuda]

Indeed! Thank you for clarifying!