Users can configure their communication preferences

[compwron]

Part of epic #1017, dependent on #1785

AS a volunteer/supervisor/admin,
I WANT to be able to customize my communication preferences,
SO THAT I receive notifications through the channels I wish to receive them.

Dev note: add a user_preferences lazy-initialize db table rows, or what works

How it works now

There is currently no place for any user to configure communication preferences since the only channel for receiving notifications was email up until #1017.

How it should work

Users should have the option of selecting the channels through which they'd like to receive notifications (at least one channel must be selected).
It should look something like this:

Acceptance criteria

• There is a new section called "Communication Preferences" under "Edit Profile"
• There is instructional text in this section reading: Tell us how you'd like to receive notifications.
• There are two options with corresponding checkboxes in this section:
  • Email me
  • Text me
• Beneath these options is a button "Save Preferences" that when clicked, will update communication preferences.
• If a user selects "Save Preferences" without selecting one option, a dialogue box appears, reading:
  One option must be selected. with the button "okay". Clicking the button closes the dialogue box and returns the user to the same screen.

[github-actions]

Stale issue message

[github-actions]

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