add rubocop-rails

[tknzk]

Changes

Fix Warning: unrecognized cop Rails found in .rubocop.yml

References

• [#5976] Warn for Rails Cops rubocop/rubocop#7071
• https://github.com/rubocop-hq/rubocop-rails

Testing

Please describe how this can be tested by reviewers. Be specific about anything not tested and reasons why. If this library has unit and/or integration testing, tests should be added for new functionality and existing tests should complete without errors.

• This change adds unit test coverage
• This change adds integration test coverage
• This change has been tested on the latest version of Ruby

Checklist

• I have read the Auth0 general contribution guidelines
• I have read the Auth0 Code of Conduct
• All existing and new tests complete without errors
• Rubocop passes on all added/modified files
• All active GitHub checks have passed

[joshcanhelp]

@tknzk - Thanks for the PR and apologies for the delay! Will this still run in a non-Rails environment?

[tknzk]

@joshcanhelp thank you for reviewing.

Will this still run in a non-Rails environment?

No problem.

rubocop-rails is RuboCop extension focused on enforcing Rails best practices and coding conventions.
( https://github.com/rubocop-hq/rubocop-rails )

config is https://github.com/auth0/ruby-auth0/blob/master/.rubocop.yml#L2-L3

[tknzk]

thanks.