fix ruby loading opal spec helpers.

how was this not failing before?

Author: ajjahn

spec/support/react/spec_helpers.rb

@@ -1,3 +1,4 @@
+if opal?
 module React
   module SpecHelpers
     `var ReactTestUtils = React.addons.TestUtils`
@@ -60,3 +61,4 @@ def expect_component_to_eventually(component_class, opts = {}, &block)
     end
   end
 end
+end