Fix staticcheck SA5011 nil pointer dereference in retriever test

[JAORMX]

This PR fixes the staticcheck linter errors that were blocking CI:

Error: pkg/runner/retriever/retriever_test.go:39:5: SA5011(related information): this check suggests that the pointer can be nil (staticcheck)
Error: pkg/runner/retriever/retriever_test.go:45:15: SA5011: possible nil pointer dereference (staticcheck)

What was the problem?

The test had two separate if statements checking for nil conditions:

1. First checking if testGroupName is empty
2. Then checking if group is nil

Both checks call t.Skip() to exit the test early. However, the staticcheck linter couldn't understand that t.Skip() terminates execution, so it thought the code could continue and potentially dereference a nil group pointer later in the test.

How did we fix it?

We combined both checks into a single if statement using the OR operator (||). This makes it crystal clear to the linter that if group is nil, the test will skip before any code tries to access group.Servers.

The test behavior is exactly the same - it still skips when there are no groups or when the group is nil. We just made the logic clearer for the static analyzer.

Verification

• ✅ Staticcheck now passes with zero SA5011 errors
• ✅ The test still works correctly and skips appropriately
• ✅ No functional changes to the test logic

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 48.20%. Comparing base (be1e1a5) to head (78ce5d2).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2050      +/-   ##
==========================================
+ Coverage   48.13%   48.20%   +0.06%     
==========================================
  Files         233      233              
  Lines       29240    29240              
==========================================
+ Hits        14075    14095      +20     
+ Misses      14133    14110      -23     
- Partials     1032     1035       +3     

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