Improve test for NOTE Remarkup rule

Test Plan:
  lang=diviner
  NOTE: Amazon SES **requires you to verify your "From" address**. Configure which
  "From" address to use by setting "##metamta.default-address##" in your config,
  then follow the Amazon SES verification process to verify it. You won't be able
  to send email until you do this!

Blame Rev: D6319

Reviewers: garoevans, epriestley

Reviewed By: epriestley

CC: aran, epriestley, btrahan, Korvin

Differential Revision: https://secure.phabricator.com/D6380