PADV-2731 fix: CSS style to email templates to make them compatible with email.

[JuanDavidBuitrago]

Description

This PR support the custom template for the enrollment email message in Ulmo version.

Email views

Browser view

Mobile view

Relates PRs:

• PADV-2235 fix: CSS style to email templates to make them compatible with email." #157
• PADV-2313 fix: Import a new .png background image to the enroll email #158
• PADV-2313 fix: Import a new .png background image to the enroll email #159
• PADV-2314 fix: Modify styles to adapt the container of enroll email with the email client #161
• PADV-2314 fix: Modify styles to adapt the container of enroll email with the email client #162
• PADV-2314 fix: Modify styles to adapt the container of enroll email with the email client (rollback). #163
• PADV-2314 fix: Modify styles to adapt the container of enroll email with the email client (recommended max-width approach). #164
• PADV-2314 fix: Modify styles to adapt the container of enroll email with the email client (replacing div with tables and manage box-sizing). #165

Issue

• https://pearson.atlassian.net/browse/PADV-2731