[w3c/webauthn] a74135: address emlun's review comment

  Branch: refs/heads/jeffh-fix-593-domstring-contents
  Home:   https://github.com/w3c/webauthn
  Commit: a74135a915c892386024082f8ea5485db87b4153
      https://github.com/w3c/webauthn/commit/a74135a915c892386024082f8ea5485db87b4153
  Author: JeffH <Jeff.Hodges@PayPal.com>
  Date:   2018-06-15 (Fri, 15 Jun 2018)

  Changed paths:
    M index.bs

  Log Message:
  -----------
  address emlun's review comment



      **NOTE:** This service been marked for deprecation: https://developer.github.com/changes/2018-04-25-github-services-deprecation/

      Functionality will be removed from GitHub.com on January 31st, 2019.