Use SSL for Postmark API

[bjester]

Summary

Description of the change(s) you made

I just got an email from Postmark stating that they're deprecating API calls via HTTP, and that we have to switch to HTTPS. Seems we have until November 30th.

Updates settings to enable POSTMARK_SSL according to this code

References

https://learningequality.slack.com/archives/C0WHZ9FPX/p1662161093351529

Comments

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