wip: Use SES to send all confirmation emails

[alice-carr]

What problem does this pull request solve?

Trello card: https://trello.com/c/GfBTJbNL/3154-blocked-until-a-sprint-after-copy-of-answers-launch-use-ses-to-send-all-confirmation-emails

We currently use SES to send confirmation emails that include a copy of the user’s answers and Notify to send confirmation emails that do not. We should switch all confirmation emails to use SES.

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