Remove `except` from blacklist of `CodeReuse/ActiveRecord`

The following discussion from !16508 (merged) should be addressed:

• @dzaporozhets started a discussion: (+2 comments)

  I don't understand why we disallow use of except method in controller. Its ActionController::Parameters method and makes total sense to use in controllers. I believe we should adjust the cop rule.

  I think its too many occurrences and it would be better if we remove except from blacklist, like we did for first, last etc. I don't see a point in rule if we are putting so many ignore places.