Update for latest rubocop

Author: twalpole

.rubocop.yml

@@ -181,3 +181,6 @@ RSpec/PredicateMatcher:
 
 RSpec/Capybara/FeatureMethods:
   Enabled: false
+
+RSpec/Capybara/NegationMatcher:
+  Enabled: false

lib/capybara/spec/session/has_css_spec.rb

@@ -1,7 +1,5 @@
 # frozen_string_literal: true
 
-# rubocop:disable RSpec/Capybara/SpecificMatcher
-
 Capybara::SpecHelper.spec '#has_css?' do
   before do
     @session.visit('/with_html')
@@ -375,5 +373,3 @@
     end
   end
 end
-
-# rubocop:enable RSpec/Capybara/SpecificMatcher