add gist id back in

Author: benbalter

spec/gist_tag_spec.rb

@@ -124,6 +124,7 @@
         doc.content = content
         doc.output  = Jekyll::Renderer.new(doc.site, doc).run
       end
+      let(:gist) { "mattr-/24081a1d93d2898ecf0f" }
 
       it "does not produce the noscript tag" do
         expect(output).to_not match(/<noscript>/)