Stabilize Diaspora::Federation::Receive.comment.saves the signature data

spec/lib/diaspora/federation/receive_spec.rb

@@ -110,7 +110,8 @@ describe Diaspora::Federation::Receive do
 
       expect(comment.signature).not_to be_nil
       expect(comment.signature.author_signature).to eq("aa")
-      expect(comment.signature.additional_data).to eq("new_property" => "data", "edited_at" => comment_entity.edited_at)
+      expect(comment.signature.additional_data["new_property"]).to eq("data")
+      expect(comment.signature.additional_data["edited_at"]).to be_within(1.second).of(comment_entity.edited_at)
       expect(comment.signature.order).to eq(comment_entity.signature_order.map(&:to_s))
     end