fix: validation error with only other for outcome analysis (resolves #2057)

[jobara]

Resolves #2057

• Allows specifying only an "other" for Who will be going through the results and producing an outcome?
• Updates publishable check to allow the project to be publishable in the above case
• Extends test coverage for validation errors related to project requests
• Addresses some issues found with the request validation when adding the tests

Prerequisites

If this PR changes PHP code or dependencies:

• [x] I've run composer format and fixed any code formatting issues.
• [x] I've run composer analyze and addressed any static analysis issues.
• [x] I've run php artisan test and ensured that all tests pass.
• [x] I've run composer localize to update localization source files and committed any changes.

If this PR changes CSS or JavaScript code or dependencies:

• [ ] I've run npm run lint and fixed any linting issues.
• [ ] I've run npm run build and ensured that CSS and JavaScript assets can be compiled.

[codecov[bot]]

Codecov Report

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

Comparison is base (b4f8c3f) 97.60% compared to head (c37d4bc) 97.65%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## dev #2104 +/- ## ============================================ + Coverage 97.60% 97.65% +0.04% - Complexity 2101 2103 +2 ============================================ Files 313 313 Lines 9522 9535 +13 ============================================ + Hits 9294 9311 +17 + Misses 228 224 -4 ```

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