Add 3 days left marketing email

[loreina]

Tickets:

List of changes:

• Add 3 days left marketing email to /marketingEmail
• Fix unsubscribe button in marketing emails

Type of change

• New feature (non-breaking change which adds functionality)

How has this been tested?

Questions for code reviewers?

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings
• Listed change(s) in the Changelog
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• I have made corresponding changes to the documentation
• Any dependent changes have been merged and published in downstream modules

[isabelledelmundo]

LGTM!