Handle unauthorized org membership check gracefully

[arnavk23]

Summary

Replace the conditional skip for org membership tests with a try-catch that gracefully handles unauthorized access (when the token lacks org permissions), skipping the test instead of erroring.

Testing

• julia --project -e 'using Pkg; Pkg.test(; test_args=["read_only_api_tests"])' passes with tokens that have org access.
• With tokens lacking org access, the test is skipped with an informative message instead of failing.

[codecov]

Codecov Report

❌ Patch coverage is 0% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 57.86%. Comparing base (97e94e4) to head (ba0afb2).

Files with missing lines	Patch %	Lines
src/owners/owners.jl	0.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #253      +/-   ##
==========================================
- Coverage   58.45%   57.86%   -0.59%     
==========================================
  Files          37       37              
  Lines         982      985       +3     
==========================================
- Hits          574      570       -4     
- Misses        408      415       +7     

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[DilumAluthge]

Thanks for splitting this out!

I think we might have to give this some thought.

So, if I understand correctly, there are three possible cases:

1. Case 1: The token is the GITHUB_TOKEN provided automatically by GitHub Actions.
2. Case 2: The token is a personal access token (PAT) for a user, and the user is a member of the JuliaWeb org.
3. Case 3: The token is a PAT for a user, and the user is not a member of the JuliaWeb org.

We already detect Case 1 - the result is stored in the is_gha_token::Bool variable.

@arnavk23 Can you write some logic to detect case 2 vs case 3, without using try-catch? You'll want to use the "List organizations for the authenticated user" API. I don't know if that API is currently supported by GitHub.jl, so it might be helpful if you could add it.

Once we have the ability to distinguish between case 2 and case 3, I think we should then use the following logic:

1. First, check if we are running in CI or not.
2. If we are running in CI:
   • If we are in case 3, throw an error. We should never hit case 3 in the CI on this repo.
   • If we are in case 2, then run the the check_membership() test.
   • • If we are in case 1 or case 3, skip the check_membership() test (with a @test_skip).
3. If we are not running in CI:
   • If we are in case 2, then run the the check_membership() test.
   • If we are in case 1 or case 3, skip the check_membership() test (with a @test_skip).

Here, when I say "the check_membership() test", I'm referring to this test:

@test GitHub.check_membership(julweb, testuser; auth = auth)

Does that make sense? This way, instead of using try-catch (which might mask an error that we actually want to surface), we can more specifically run or skip the test based on the specific circumstances.