JIRA Service Desk email content is not center-aligned in Outlook 2013.

Steps to reproduce

1. Disable sd.email.conversational.notification.disabled in the dark feature to remove the pre-populate text as stated in this bug ticket: https://jira.atlassian.com/browse/JSD-2257
2. Create a Service Desk customer and use outlook email address for the customer's email address
3. Create a Service Desk ticket using the newly created customer
4. Use Outlook 2013 to check your inbox

Expected Result
The email content is in aligned correctly

Actual Result
The email content is not center-aligned like how it used to.