Bump yard to support Ruby 2.7

See: https://github.com/lsegal/yard/releases/tag/v0.9.21

- Avoid a bug with a yard and source code not well rendered by bumping
redcarpet version
- To avoid loosing big comment in yard we need to have blank line

This is not needed to provide this option

Author: benoittgt

Gemfile

@@ -20,12 +20,12 @@ else
   gem 'rake', '< 11.0.0' # rake 11 requires Ruby 1.9.3 or later
 end
 
-gem 'yard', '~> 0.9.12', :require => false
+gem 'yard', '~> 0.9.24', :require => false
 
 ### deps for rdoc.info
 group :documentation do
-  gem 'redcarpet',     '2.1.1', :platform => :mri
-  gem 'github-markup', '0.7.2', :platform => :mri
+  gem 'redcarpet', :platform => :mri
+  gem 'github-markup', :platform => :mri
 end
 
 if RUBY_VERSION < '2.0.0' || RUBY_ENGINE == 'java'

lib/rspec/core/formatters.rb

@@ -1,4 +1,5 @@
 RSpec::Support.require_rspec_support "directory_maker"
+
 # ## Built-in Formatters
 #
 # * progress (default) - Prints dots for passing examples, `F` for failures, `*`