update_credentials should not update the kind 0 unless it would actually be changed

See: https://gleasonator.dev/@npub1wf4pufsucer5va8g9p0rj5dnhvfeh6d8w0g6eayaep5dhps6rsgs43dgh9/posts/b64d82aacb9212b5ae1ef7a98c9a41e18371946182be691bb28b9a421e8da738

Sometimes we do PATCH update_credentials with just settings_store, for example. We still update the kind 0 in that case for no good reason. We should only update the kind 0 if the user sets values through the Edit Profile screen.