Enable Layout/SpaceBeforeBrackets cop

[yahonda]

This pull request enables Layout/SpaceBeforeBrackets cop, which has not been enabled at rails/rails repository. Actually, Rails code does not have any offenses detected by this cop then I have no plan to open a pull request to Rails repository to enable it.

This cop should work with RuboCop 1.8 which includes rubocop/rubocop#9291

$ bundle exec rubocop -a
Inspecting 71 files
...........................C...........................................

Offenses:

lib/active_record/connection_adapters/oracle_enhanced_adapter.rb:495:39: C: [Corrected] Layout/SpaceBeforeBrackets: Remove the space before the opening brackets.
          @do_not_prefetch_primary_key [table_name] = do_not_prefetch = !has_primary_key?(table_name, owner, desc_table_name)
                                      ^

71 files inspected, 1 offense detected, 1 offense corrected

Tip: Based on detected gems, the following RuboCop extension libraries might be helpful:
  * rubocop-rake (http://github.com/rubocop-hq/rubocop-rake)
  * rubocop-rspec (http://github.com/rubocop-hq/rubocop-rspec)

You can opt out of this message by adding the following to your config (see https://docs.rubocop.org/rubocop/extensions.html#extension-suggestions for more options):
  AllCops:
    SuggestExtensions: false
$

Refer rubocop/rubocop#9305

[yahonda]

@koic I did not explain the background for asking for a review for this pull request.
Usually, Oracle enhanced adapter .rubocop.yml follows that of Rails configuration but this one is kind of exception.

[koic]

TBH, I'm not sure if it's better to make an exception (enhanced) rule. I get it that Layout/SpaceBeforeBrackets cop doesn't registered an offense in Rails repo, but can you consider proposing to enable the cop to Rails repo for preparing the future?
Of course I don't have a strong opinion, so I think I could merge this without proposing it to Rails.

[yahonda]

Thanks for the review and comment. Yeah, let me consider to propose this cop to Rails repository.

[yahonda]

I'm going to merge this pull request.