Fix AddWhenAndYamlVariablesToCiBuilds migration

db/migrate/20160716115710_add_when_and_yaml_variables_to_ci_builds.rb

 # See http://doc.gitlab.com/ce/development/migration_style_guide.html
 # for more information on how to write migrations for GitLab.
 
-class AddWhenAndYamlVariablesCiBuilds < ActiveRecord::Migration
+class AddWhenAndYamlVariablesToCiBuilds < ActiveRecord::Migration
   include Gitlab::Database::MigrationHelpers
 
   # When using the methods "add_concurrent_index" or "add_column_with_default"