feat: update sharable testimonials models

[archx3]

Summary / Highlights

Rerun migration and added approved_for_sharing_by field to track community approval status for testimonials. Updated sharing type choices to more consistent naming in both the testimonial model and the enums file.

Details (Give details about what this PR accomplishes, include any screenshots etc)

Testing Steps (Provide details on how your changes can be tested)

Requirements (place an x in each [ ])

• [x] I've read and understood the Contributing Guidelines and have done my best effort to follow them.
• [ ] I've tested my changes manually.
• [ ] I've added unit tests to my PR.

Transparency (Project board)

• [x] I've given my PR a meaningful title.
• [ ] I linked this PR to the relevant issue.
• [ ] I moved the linked issue from the "Sprint backlog" to "In progress" when I started this.
• [ ] I moved the linked issue to "QA Verification" now that it is ready to merge.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 56.45%. Comparing base (50fee7e) to head (3d61f44). Report is 1 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1161 +/- ## ========================================== - Coverage 56.45% 56.45% -0.01% ========================================== Files 470 470 Lines 34432 34433 +1 ========================================== - Hits 19440 19439 -1 - Misses 14992 14994 +2 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.