Fix spec for parsing invalid JSON

The cookie adapter uses string as a key, so should the spec. Also, context.request.cookies is a hash
in both cases, it feels that it should be set directly, not using a hash with "value" and "expires" keys.

Author: knarewski

spec/persistence/cookie_adapter_spec.rb

@@ -14,10 +14,8 @@
       end
 
       it "handles invalid JSON" do
-        context.request.cookies[:split] = {
-          value: '{"foo":2,',
-          expires: Time.now
-        }
+        context.request.cookies["split"] = "{\"foo\":2,"
+
         expect(subject["my_key"]).to be_nil
         subject["my_key"] = "my_value"
         expect(subject["my_key"]).to eq("my_value")