Add `Style/RedundantFreeze` to remove redudant `.freeze`

Since Rails 6.0 will support Ruby 2.4.1 or higher
`# frozen_string_literal: true` magic comment is enough to make string object frozen.
This magic comment is enabled by `Style/FrozenStringLiteralComment` cop.

* Exclude these files not to auto correct false positive `Regexp#freeze`
 - 'actionpack/lib/action_dispatch/journey/router/utils.rb'
 - 'activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb'

It has been fixed by https://github.com/rubocop-hq/rubocop/pull/6333
Once the newer version of RuboCop released and available at Code Climate these exclude entries should be removed.

* Replace `String#freeze` with `String#-@` manually if explicit frozen string objects are required

 - 'actionpack/test/controller/test_case_test.rb'
 - 'activemodel/test/cases/type/string_test.rb'
 - 'activesupport/lib/active_support/core_ext/string/strip.rb'
 - 'activesupport/test/core_ext/string_ext_test.rb'
 - 'railties/test/generators/actions_test.rb'

1 files changed, 2 insertions, 2 deletions

diff --git a/actionpack/lib/action_dispatch/http/url.rb b/actionpack/lib/action_dispatch/http/url.rb
index db6d8188d3..3af4c176a7 100644
--- a/actionpack/lib/action_dispatch/http/url.rb
+++ b/actionpack/lib/action_dispatch/http/url.rb
@@ -67,7 +67,7 @@ module ActionDispatch
         end
 
         def path_for(options)
-          path = options[:script_name].to_s.chomp("/".freeze)
+          path = options[:script_name].to_s.chomp("/")
           path << options[:path] if options.key?(:path)
 
           add_trailing_slash(path) if options[:trailing_slash]
@@ -231,7 +231,7 @@ module ActionDispatch
       #   req = ActionDispatch::Request.new 'HTTP_HOST' => 'example.com:8080'
       #   req.host # => "example.com"
       def host
-        raw_host_with_port.sub(/:\d+$/, "".freeze)
+        raw_host_with_port.sub(/:\d+$/, "")
       end
 
       # Returns a \host:\port string for this request, such as "example.com" or