Update Redcarpet to 3.5.1 (#34461).

The version fixes a security vulnerability using :quote in combination with the :escape_html option.


git-svn-id: http://svn.redmine.org/redmine/trunk@20665 e93f8b46-1217-0410-a6f0-8f06a7374b81

Author: vividtone

Gemfile

@@ -44,7 +44,7 @@ end
 
 # Optional Markdown support, not for JRuby
 group :markdown do
-  gem "redcarpet", "~> 3.5.0"
+  gem 'redcarpet', '~> 3.5.1'
 end
 
 # Include database gems for the adapters found in the database