DRY it out a little

spec/create_spec.rb

@@ -19,8 +19,9 @@ describe "Submit API request to create new link" do
     }
     post('/create', data.to_json, "CONTENT_TYPE" => "application/json")
     expect(last_response).to be_ok
-    expect(JSON.parse(last_response.body)['url']).to eq(data[:url])
+    response_json = JSON.parse(last_response.body)
-    expect(JSON.parse(last_response.body)['code']).not_to eq(nil)
+    expect(response_json['url']).to eq(data[:url])
+    expect(response_json['code']).not_to eq(nil)
   end
 end