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:

• I've run composer format and fixed any code formatting issues.
• I've run composer analyze and addressed any static analysis issues.
• I've run php artisan test and ensured that all tests pass.
• 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]

Codecov Report

All modified and coverable lines are covered by tests ✅

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

Additional details and impacted files

@@             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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