fix: correct fallback handling for email opt-in report

[ajayakkalasetti]

Summary

Fixes incorrect fallback behavior in the Email Opt-In report where users without an email preference record were assigned misleading default values.

Problem

The report currently assigns:

• is_opted_in_for_email = "True" (hardcoded)
• preference_set_datetime = "2014-12-01 00:00:00" (hardcoded default)

when no corresponding record exists in user_api_userorgtag.

Solution

• Removed the hardcoded fallback date

• Avoid defaulting is_opted_in_for_email to "True"

• Instead:

  • Leave preference_set_datetime empty when no value exists
  • Leave is_opted_in_for_email empty when no preference is set

  Amal please take a look on it.