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/actionview/test/template/text_helper_test.rb b/actionview/test/template/text_helper_test.rb
index c4e420a95b..2925489f5d 100644
--- a/actionview/test/template/text_helper_test.rb
+++ b/actionview/test/template/text_helper_test.rb
@@ -34,10 +34,10 @@ class TextHelperTest < ActionView::TestCase
     assert_equal "<p>A paragraph</p>\n\n<p>and another one!</p>", simple_format("A paragraph\n\nand another one!")
     assert_equal "<p>A paragraph\n<br /> With a newline</p>", simple_format("A paragraph\n With a newline")
 
-    text = "A\nB\nC\nD".freeze
+    text = "A\nB\nC\nD"
     assert_equal "<p>A\n<br />B\n<br />C\n<br />D</p>", simple_format(text)
 
-    text = "A\r\n  \nB\n\n\r\n\t\nC\nD".freeze
+    text = "A\r\n  \nB\n\n\r\n\t\nC\nD"
     assert_equal "<p>A\n<br />  \n<br />B</p>\n\n<p>\t\n<br />C\n<br />D</p>", simple_format(text)
 
     assert_equal '<p class="test">This is a classy test</p>', simple_format("This is a classy test", class: "test")