Fix rdoc task name (closes #10392) [murphy]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@8427 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

Rakefile

@@ -11,7 +11,7 @@ end
 desc 'Run all tests by default'
 task :default => :test
 
-%w(test docs package pgem release).each do |task_name|
+%w(test rdoc package pgem release).each do |task_name|
   desc "Run #{task_name} task for all projects"
   task task_name do
     PROJECTS.each do |project|