Give user ability to enable/disable SMS notifications

[talya19]

What type of user is this for? volunteer/supervisor/admin/all
Volunteer and supervisor

Description
We can't send SMS notifications yet but at this time we'd like to store the user preference in the database

• User can enable SMS notifications
• User can disable SMS notifications if email notifications are enabled.
• If volunteer has deactivated email notifications, they cannot deactivate SMS notifications (to be validated with Francha from Montgomery).

Screenshots of current behavior, if any
Currently, user receives notifications via email only.

User Acceptance criteria:

QA Login Details:
url: https://casa-qa.herokuapp.com/
password for all users: 12345678

Log in using any of the below emails, depending on the account type you'd like to log in as.

• volunteer1@example.com
• supervisor1@example.com
• casa_admin1@example.com

[github-actions]

This issue has been open without changes for a long time! What's up?

[compwron]

We want to build this before actually sending SMS notifications, so users have a chance to change settings before getting messages

[compwron]

Put it under a feature flag! This will be the first use of feature flags in our codebase :)

[github-actions]

This issue has been open without changes for a long time! What's up?

[FireLemons]

I'm copying the text from this into a card