Option to ignore unrecognized cop / department

[fschwahn]

Is your feature request related to a problem? Please describe.

We are using githubs superlinter (https://github.com/github/super-linter) for linting in our projects. The superlinter sometimes lags behind the current rubocop version for a few weeks (eg. current latest release is from April 1st - there have been 6 new rubocop versions in that time).

However, developers update rubocop more often locally, and run into cops we might not want to enforce, so we update our central rubocop config to disable / tweak rules. However, now github superlinter fails because we include configuration which it doesn't understand yet due to being on an older version of rubocop.

Describe the solution you'd like

An option to opt-out of errors in case of unrecognized cops. The default could stay as is.

Describe alternatives you've considered

I though about disabling NewCops - but that's not really something we want to do, we just want to opt-out of cops which don't fit our use cases.

[fschwahn]

Oh wow, thanks. That was a quick turnaround - now I just have to get superlinter to pick up this option 😄